Bothriolepid Antiarchs (Vertebrata, Placodermi) from the Devonian of the North-Western Part of the East European Platform

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Bothriolepid antiarchs (Vertebrata, Placodermi) from the Devonian of the north-western part of the East European Platform

Erwin LUKŠEVIČS Institute of Geology, University of Latvia, Rainis Blvd 19 Rīga LV 1586 (Latvia) [email protected] [email protected]

Lukševičs E. 2001. — Bothriolepid antiarchs (Vertebrata, Placodermi) from the Devonian of the north-western part of the East European Platform. Geodiversitas 23 (4) : 489-609.

ABSTRACT A large collection of bothriolepid antiarch material from 26 localities in the north-western part of the East European Platform (Latvia, Lithuania, and the Leningrad, Novgorod, and Pskov regions of Russia) is described and illustrated, with a critical treatment of previously described material. The genus Grossilepis Stensiö, 1948 is represented by two species, Grossilepis tuberculata (Gross, 1941) and G. spinosa (Gross, 1942). All remaining material is referred to the genus Bothriolepis Eichwald, 1840: B. prima Gross, 1942, B. obrutschewi Gross, 1942, B. cellulosa (Pander in Keyserling, 1846), B. panderi Lahusen, 1880, B. traudscholdi Jaekel, 1927, B. maxima Gross, 1933, B. evaldi Lyarskaja, 1986 come from the Givetian(?)-Frasnian deposits, and B. leptocheira curonica Gross, 1942, B. ornata Eichwald, 1840, B. jani Lukševičs, 1986, B. heckeri n. sp., B. ciecere Lyarskaja in Lyarskaja & Savvaitova, 1974 as well as one unnamed form come from the Famennian KEY WORDS sequence. The stratigraphic distribution of bothriolepids through the Vertebrata, Placodermi, Middle/Upper Devonian of the Main Devonian Field is clarified in a proposed antiarchs, new version of the vertebrate zonation. A cladistic analysis of the distribution Devonian, Baltic area, of several features within the family Bothriolepididae using the PHYLIP pro- biostratigraphy. gram package provides a new version of the interrelationships of bothriolepids.

GEODIVERSITAS • 2001 • 23 (4) © Publications Scientifiques du Muséum national d’Histoire naturelle, Paris. www.mnhn.fr/publication/ 489 Lukševičs E.

RÉSUMÉ Bothriolépides antiarches (Vertebrata, Placodermi) du Dévonien du nord- ouest de la plateforme est-européenne. Une large collection de Bothriolepididae de 26 gisements du nord-ouest de la plateforme est-européenne (Lettonie, Lithuanie, régions de Leningrad, Novgorod et Pskov de la Russie) est étudiée et figurée, avec un traitement cri- tique du matériel précédemment décrit. Le genre Grossilepis Stensiö, 1948 est représenté par deux espèces : Grossilepis tuberculata (Gross, 1941) et G. spinosa (Gross, 1942). Le reste du matériel est attribué au genre Bothriolepis Eichwald, 1948 : B. prima Gross, 1942, B. obrutschewi Gross, 1942, B. cellulosa (Pander in Keyserling, 1846), B. panderi Lahusen, 1880, B. traudscholdi Jaekel, 1927, B. maxima Gross, 1933, B. evaldi Lyarskaja, 1986 du Givétien (?)-Frasnien, et B. leptocheira curonica Gross, 1942, B. ornata Eichwald, 1840, B. jani Lukševičs, 1986, B. heckeri n. sp., B. ciecere Lyarskaja in Lyarskaja & Savvaitova, 1974, et MOTS CLÉS Vertebrata, une forme non nommée d’âge famennien. La répartition stratigraphique des Placodermi, Bothriolepididae du Dévonien moyen et supérieur du Champ Dévonien antiarches, Principal et une nouvelle division en zones ichthyologiques sont proposées. Une Dévonien, Baltique, analyse cladistique des Bothriolepidae utilisant le logiciel PHYLIP a déjà fourni biostratigraphie. une nouveau scheme de relations de parenté des bothriolépides.

CONTENTS

Introduction ...... 491 Technique and terminology ...... 491 Historical account ...... 494 Distribution and biostratigraphy ...... 497 Lithologies, facies variations and vertebrate assemblages ...... 499 Systematics ...... 505 Bothriolepis prima Gross, 1942 ...... 505 Bothriolepis obrutschewi Gross, 1942 ...... 510 Bothriolepis cellulosa (Pander in Keyserling, 1846) ...... 517 Bothriolepis panderi Lahusen, 1880 ...... 519 Bothriolepis traudscholdi Jaekel, 1927 ...... 521 Bothriolepis maxima Gross, 1933 ...... 534 Bothriolepis evaldi Lyarskaja, 1986 ...... 539 Bothriolepis leptocheira Traquair, 1893 ...... 544 Bothriolepis ornata Eichwald, 1840 ...... 554 Bothriolepis jani Lukševičs, 1986 ...... 569 Bothriolepis heckeri n. sp...... 577 Bothriolepis ciecere Lyarskaja in Lyarskaja & Savvaitova, 1974 ...... 578 Bothriolepis sp. indet. 1 ...... 594 Grossilepis Stensiö, 1948 ...... 595 Grossilepis tuberculata (Gross, 1941) ...... 595 Grossilepis spinosa (Gross, 1942) ...... 598 Interrelationships of Baltic bothriolepids ...... 598 Acknowledgements ...... 603 References ...... 604 Appendix...... 609

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INTRODUCTION describe and illustrate the armour structure of each species as completely as possible, because The family Bothriolepididae Cope, 1886 is the the members of the genus Bothriolepis are con- most diverse group of antiarchs in the western siderably variable in the shape of individual part of the East European Platform, represented plates and their overlap patterns as well as in the by at least 15 taxa. Subdivision of the Upper course of sensory line canals. Devonian of the Baltic region and north-west- The largest part of studied and described speci- ern part of Russia is based largely on fish data. mens was collected by J. Blesse, L. Lyarskaja, Bothriolepididae are very important for the cor- W. Gross, N. Delle, V. Sorokin, J. Upenieks and relation of Frasnian and Famennian deposits of the author, and is housed in the Latvian the Main Devonian Field of the East-European Museum of Natural History (Rīga). Other stud- Platform with similar strata elsewhere. The ied material is in the Paleontological Institute, genus Bothriolepis is of particular interest as it is Moscow (coll. D. Obruchev, R. Hecker, found in the Middle and Late Devonian deposits J. Eglons, N. Krupina, F. Chernyshov); Institute on all continents. of Geology of Lithuania, Vilnius (coll. Gross (1933, 1941, 1942), Lyarskaja (1978, 1981, V. Talimaa); Mining Museum, Saint-Petersburg 1986), Obruchev (1928, 1947, 1958, 1964), (coll. H. Helmersen, I. Lahusen, A. Olivieri); Karatajūte-Talimaa (1963, 1966) and others pro- Institute of the Earth Crust, St.-Petersburg (coll. vided lists of agnathans and fishes characteristic A. Ivanov, W. Ermolaew, S. Snigirevsky); for various Devonian beds in the Baltic and Museum of Geology of the University of Latvia, north-western part of Russia, described verte- Rīga (coll. N. Delle, R. Kampe); Natural brate assemblages and correlated some strata History Museum, London (coll. P. Egerton, with the Upper Devonian of other regions. Six J. Eglons, R. Gross); and the National Museum new species have been described from the Main of Scotland, Edinburgh (coll. R. Gross, Devonian Field since Stensiö’s (1948) major H. Trautschold, J. V. Rohon). revision of the Bothriolepididae. During preparation of this work, a large amount of bothriolepidid remains stored in the main museums of TECHNIQUE AND TERMINOLOGY Latvia, Lithuania, Russia and Great Britain was studied. A large amount of new material has Antiarch remains from the Main Devonian Field been excavated which provided opportunity to are found only rarely as whole skeletons (in four revise the structure and distribution of localities only). Well-preserved complete armour Bothriolepis and Grossilepis and correlate of Bothriolepis evaldi Lyarskaja, 1986 was found deposits of various regions. This paper presents by V. Sorokin for the first time and then several the revision of such poorly known species as were collected by L. Lyarskaja from an outcrop at Bothriolepis panderi Lahusen, 1880, B. traud- the Amula River downstream from Kalnamuiža scholdi Jaekel, 1927 and B. ornata Eichwald, watermill (Lyarskaja 1986). Prof. D. Obruchev 1840 among 16 taxa of Bothriolepis and collected whole specimens of B. traudscholdi Grossilepis from the Main Devonian Field which Jaekel at the Syas’ River near Stolbovo village. have been named and described below, includ- Any skeletal elements behind the trunk armour ing Bothriolepis leptocheira curonica Gross, are not preserved in Bothriolepis material from 1942, moved down to the rank of subspecies. the Main Devonian Field. The placoderm fish material from Latvia and Since 1981, the author has collected numerous Lithuania comprises numerous well-preserved disarticulated bones of Bothriolepis as well as disarticulated plates, as well as complete head remains of other fossil vertebrates from 26 local- shields and portions of articulated trunk ities on the Abava, Amula, Ciecere, Daugava, armours. The purpose of this work was to Gauja, Imula, Kaibala, Roja, Skujaine, Svēte,

GEODIVERSITAS • 2001 • 23 (4) 491 Lukševičs E.

FIG. 1. — Localities of the Main Devonian Field studied by the author and/or mentioned in the text; 1, Ketleri: Bothriolepis ciecere Lyarskaja in Lyarskaja & Savvaitova, 1974; 2, Pavāri: Bothriolepis ciecere; 3, Bienes: Bothriolepis leptocheira curonica Gross, 1942; 4, Kalnarāji: Bothriolepis maxima Gross, 1933; 5, Kalnamuiža 1: Bothriolepis evaldi Lyarskaja, 1986; 6, Kalnamuiža 2: Bothriolepis sp. (in Amula Formation), Bothriolepis leptocheira curonica (in Eleja Formation); 7, Velna Ala: Bothriolepis maxima, Grossilepis spinosa (Gross, 1942); 8,Klūnas: Bothriolepis ornata Eichwald, 1840, B. jani Luksevics, 1986; 9, Ķurbes: Bothriolepis jani; 10, Ceraukste: Bothriolepis maxima; 11, Lielvārde: Bothriolepis maxima, Bothriolepis sp.; 12, Kaibala: Bothriolepis evaldi; 13, Koknese: Bothriolepis cellulosa (Pander in Keyserling, 1846), Grossilepis tuberculata (Gross, 1941); 14, Pastamuiža: Bothriolepis prima Gross, 1942 and B. obrutschewi Gross, 1942: in Amata Formation; B. cellulosa: in Pļaviņas Formation; 15, Jēkabpils: Bothriolepis sp.; 16, Pelyša: Bothriolepis prima, B. obrutschewi; 17, Vidaga: Bothriolepis traudscholdi Jaekel, 1927; 18, Katleši: Bothriolepis maxima; 19, Kuprava: Bothriolepis cf. maxima; 20, Piskovichi: Bothriolepis obrutschewi; 21, Yam-Tesovo: Bothriolepis prima; 22, Kurskoye Gorodische: Bothriolepis maxima (Obruchev 1947); 23, Luka: Bothriolepis maxima (Obruchev 1947); 24, Bilovo: Bothriolepis sp.; 25, Lyubitino: Bothriolepis ornata (Eichwald 1860); 26, Zarubino: Bothriolepis sp. indet. 1; 27, Paluitsa: Bothriolepis maxima (Ivanov & Khozatsky 1986); 28, Montsevo: Bothriolepis panderi Lahusen, 1880; 29, Stolbovo: Bothriolepis traudscholdi; 30, Andoma Hill: Bothriolepis sp. Dotted line outlines distribution of the Devonian rocks on the subquaternary surface of the Main Devonian Field. The Devonian deposits are not presented to the north of the line, and are covered by the youngest rocks to the south and east.

Šķēde, Venta Rivers, Lode and Jēkabpils quar- Mounted needles and stomatological equipment ries in Latvia, Skaistgiris quarry in Lithuania, were normally used. The chemical methods, Syas’, Velikaya and Priksha Rivers in Russia such as preparation in 7-10% acetic acid solu- (Leningrad, Novgorod and Pskov regions) tion, were used in some cases. (Fig. 1). During the field work, the investigations Outline drawings were mostly prepared from of fossil fish and agnathan localities were made the specimen photos. The photos are usually applying the methods suggested by Efremov taken from unprocessed specimens, magnium (1940), taphonomical features were described oxide or ammonium chloride has been used as following the scheme proposed by E. Kurik contrasting agent in some cases. Small object (Lyarskaja 1981). photos were taken using an MFN-5 appliance.

492 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

TABLE 1. — Number of measured specimens of bothriolepid taxa, used in statistical analysis. Abbreviations: B., Bothriolepis; G., Grossilepis; ADL, anterior dorso-lateral plate; AMD, anterior median dorsal plate; AVL, anterior ventro-lateral plate; CD1, dorsal central plate 1; CV1, ventral central plate; La, lateral plate; ML2, lateral marginal plate 2; MxL, mixilateral plate; Nu, nuchal plate; PMD, posterior median dorsal plate; Pn, paranuchal plate; Prm, premedian plate; PVL, posterior ventro-lateral plate.

Prm La Nu Pn AMD PMD ADL MxL AVL PVL CD1 CV1 ML2

B. cellulosa (Pander in Keyserling, 1846) 9 7 10 7 8 8 – – – – 5 – – B. ciecere Lyarskaja in Lyarskaja & Savvaitova, 1974 8 13 22 12 21 12 14 30 13 25 18 9 9 B. evaldi Lyarskaja, 1986 8 8 10 9 11 11 7 7 5 5 5 – 7 B. jani Lukševičs, 1986 – – 6 – 6 5 – 7 – – – – 5 B. leptocheira Traquair, 1893 12 13 15 17 6 – – 10 7 5 5 5 6 B. maxima Gross, 1933 7 6 10 6 17 9 9 6 6 8 – 5 – B. obrutschewi Gross, 1942 14 11 8 8 18 24 10 10 – 5 14 7 – B. ornata Eichwald, 1840 – 6 7 5 10 9 – 5 – – – – – B. prima Gross, 1942 – – – – – – – 12 – 13 5 – 6 B. traudscholdi Jaekel, 1927 12 16 21 13 19 24 12 11 14 7 – 8 5 G. tuberculata (Gross, 1941) – – 7 6 7 10 – – – – – – –

Measurements were taken with vernier calipers AVL anterior ventro-lateral plate; usually on original specimens. For number of ad1, 2 anterior and posterior articular processes on Sm; statistically analysed measured specimens see alc antero-lateral angle of head-shield; Table 1; in cases when the number of measured alr postlevator thickenings of AMD; specimens not exceeds four it is expressed as n in a1Sm anterior attachment area for Sm; brackets in the text. a2Sm posterior attachment area for Sm; a.un unornamented area beneath fossa articu- Shape and proportions of the whole armour laris pectoralis; were studied by a method suggested by CD1-5 dorsal central plates 1 to 5; Karatajūte-Talimaa (1963) using plasticine CV1-4 ventral central plates 1 to 4; reconstructions. c.al antero-lateral corner of subcephalic division of ventral lamina of AVL; Stensiö’s (1948) terminology for the bones of cd dorsal crest of AMD; Antiarchi is adopted here with some slight alter- cf.ADL area overlapping ADL; ations suggested by Miles (1968) and Young cf.AMD area overlapping AMD; (1984b) for bothriolepid cheek and jaw plates. cf.AVL area overlapping AVL; cf.MV area overlapping MV; cf.MxL area overlapping MxL; ABBREVIATIONS cf.PVL area overlapping PVL; cir semicircular pit-line groove; GM Mining Museum, Saint-Petersburg; cit1 crista transversalis interna anterior; IEC Institute of the Earth Crust, Saint- cit2 transverse thickening on the visceral sur- Petersburg; ī face of AVL; LDM Latvian Museum of Natural History, R ga; cm1 anteromesial corner of ventral lamina of LGI Institute of Geology of Lithuania, Vilnius; PVL; LUGM Museum of Geology of the University of cm2 middle corner of ventral lamina of PVL; ī Latvia, R ga; cri infra-articular crista of ADL; NHM The Natural History Museum, London; crs supra-articular crista of ADL; PIN Paleontological Institute of the Russian cr.o median occipital crista of head-shield; Academy of Sciences, Moscow; cr.pl postlevator crista of AMD; RSM National Museums of Scotland, Edinburgh; cr.pm paramarginal crista of head-shield; SMNH Swedish Museum of Natural History, cr.pto postorbital crista of head-shield; Stockholm; cr.tp crista transversalis interna posterior; ADL anterior dorso-lateral plate; cr.tv transverse nuchal crista of head-shield; AMD anterior median dorsal plate; csl central sensory line groove;

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cu postero-ventral ornamented corner of MxL; orb orbital margin; d dorsal corner of MxL; Pi pineal plate; dc dorsal corner of lateral lamina of AVL and PDL posterior dorso-lateral plate; PVL; PL posterior lateral plate; d.end opening of canal for endolymphatic duct; PMD posterior median dorsal plate; dlg1, 2 anterior and posterior oblique dorsal sen- Pmg postmarginal plate; sory line grooves; Pn paranuchal plate; dlm dorsal lamina of ADL; Pp postpineal plate; dlr dorso-lateral ridge of trunk armour; Prl prelateral plate; dma tergal angle of trunk armour; Prm premedian plate; dmr dorsal median ridge of trunk armour; prp posterior process of AMD; dxp dorso-ventral pit-line groove; PVL posterior ventro-lateral plate; f.ap fossa articularis pectoralis; p lateral pit of head-shield; f.art articular fossa of ADL; pa posterior corner of PMD; f.ax axillary foramen of AVL; p.br processus brachialis; fe.orb orbital fenestra; pc postero-lateral corner of Nu; f.mp protractor area of processus brachialis; pe pars pedalis of processus brachialis; fp funnel pit of processus brachialis; plc postero-lateral corner of PMD; f.retr levator fossa of AMD; pma posterior marginal area of PMD; g paired pits on Pp; pnn nasal notch on orbital margin of Prm; grm ventral median groove on dorsal wall of pnoa postnuchal ornamented corner of ADL; trunk armour; prc prepectoral corner of AVL; gr.sc groove, possible for sensory canal; prh preorbital recess of head-shield; ifc1 principal section of infraorbital sensory pro processus obstans of trunk armour; line on head-shield; pr.po antero-lateral corner of otico-occipital ifc2 branch of infraorbital sensory line diverg- depression; ing on La; pr.pl external postlevator process of AMD; La lateral plate; prv1 anterior ventral process of dorsal wall of l lateral corner of PMD; trunk armour; lc lateral corner of AMD; prv2 posterior ventral process of dorsal wall of lcg main lateral line groove; trunk armour; llm lateral lamina of ADL; pt1 anterior ventral pit of dorsal wall of trunk lpr lateral process of head-shield; armour; ML2-5 lateral marginal plates 2 to 5; pt2 posterior ventral pit of dorsal wall of trunk MM1-3 mesial marginal plates 1 to 3; armour; MV median ventral plate; Ro rostral plate; MxL mixilateral plate; SCLR1, 2 plates 1 and 2 of sclerotic ring; mc lateral corner of Nu; SM semilunar plate; m.lim margo limitans of AVL; Sm submarginal plate; mp middle pit-line groove; sgp pectoral pit-line groove; mppr posterior process on Nu; sna supranuchal area of AMD; mr median ridge of Pp and Prm; soc anterior section of the supraorbital sensory mvr median ventral ridge of dorsal wall of line on Prm; trunk armour; socc supraoccipital cross-commissural pit-line Nu nuchal plate; groove; nm obtected nuchal area of head-shield; sot supraotic thickening of head-shield; npl postlevator notch; T terminal plate; npn postnuchal notch of AMD; tb ventral tuberosity of dorsal wall of trunk npp postpineal notch of Nu; armour; nprl prelateral notch of head-shield; tlg transverse lateral groove of head-shield; n.prpl notch in dorsal margin of ADL for external vlr ventro-lateral ridge of trunk armour. postlevator process of AMD; oa.ADL area overlapped by ADL; oa.AMD area overlapped by AMD; HISTORICAL ACCOUNT oa.AVL area overlapped by AVL; oa.MxL area overlapped by MxL; The generic name Bothriolepis was introduced oa.PMD area overlapped by PMD; oa.PVL area overlapped by PVL; by Eichwald (1840) during the description of ood otico-occipital depression of head-shield; materials collected by H. Helmersen and

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TABLE 2. — Determination of some specimen from Baltic and Russia, described and referred to Bothriolepis favosa by Agassiz 1844-45.

Collector Plate and figure Locality Correct determination

Unknown pl. 27, fig. 7; pl. 28, fig. 12 Russia Sarcopterygian lower jaw Unknown pl. 28, fig. 13; pl. 30A, fig. 13 Russia Sarcopterygia Keyserling pl. 31A, fig. 32 Saint-Petersburg region Sarcopterygian operculum(?) Murchison pl. 31A, fig. 33 Chudovo, Russia Bone fragment Murchison pl. 31A, fig. 34 Megra, Russia Bone fragment Murchison pl. 31A, fig. 35 Prusino, Russia Bone fragment

A. Olivieri. Eichwald mentioned Holoptychius and that B. ornata (Andrews 1982: pl. 29, figs 3-5) nobilissimus Agassiz, 1839 and two new taxa, actually are B. gigantea from Monachty Hill “Asterolepis” and Bothriolepis ornata, but near Elgin, Scotland. Other plates (see Table 2) neither illustrated any samples nor indicated pre- show fragments of “crossopterygian” lower cise localities. Helmersen (1840; see Karatajūte- jaws, “crossopterygian” operculum(?), and Talimaa 1963) noted that these fish remains were small indeterminable pieces of bones with more sampled between Il’men’ and Seliger Lakes and or less pronounced tubercular ornamentation, at the Msta River, but labels of Bothriolepis orna- described by Agassiz as B. favosa. This specific ta specimens from the A. Olivieri collection in name should be therefore treated as a nomen the Mining Museum (Saint-Petersburg) also give dubium and rejected from the list of Bothriolepis a locality at the Priksha River near Borovichi valid names as it is not based on placoderm fish. town in the Novgorod region. Pander described a new antiarch species from Eichwald (1840) also mentioned Asterolepis the Upper Devonian marls of Latvia as ornata Eichwald, 1840 and Bothriolepis prisca Pterichthys cellulosa Pander in Keyserling, 1846 Eichwald, 1840 (original transcription) from the which was referred by Gross (1932) to sandstone exposed near Il’men’ Lake, and Bothriolepis. Later, Pander (1857) mixed some B. prisca from the Priksha River, but again with- plates of Bothriolepis in the description of out detailed description of these taxa. Later Asterolepis ornata, and apparently did not rec- B. priscus = prisca? was described from the ognize the differences between these two genera Middle Devonian deposits at Slavyanka River (e.g., the pectoral fin bone, Pander 1857: pl. 7, near Pavlovsk town in the vicinity of Saint- fig. 23). Specimens in Pander’s collection GM Petersburg (Eichwald 1844b). After studying 119, determined by him as Coccosteus sp. (GM the specimens, I agree with Obruchev’s opinion 1/119, 2/119) and Asterolepis sp. (GM 7/119- (in Karatajūte-Talimaa 1963) to consider that 9/119), have been determined by the author as these remains would belong to Coccosteidae. the remains of B. panderi (1/119, 2/119, 7/119, In his monograph on the Devonian fishes of the fragments of AVL; 8/119 and 9/119, pieces of Great Britain and Russia, Agassiz (1844-1845) pectoral fin bones). described Bothriolepis ornatus Eichwald, 1840 Eichwald (1860) listed the diagnostic features and B. favosa Agassiz, 1844 among others. The for these genera, several species of Asterolepis, remains of B. ornatus are shown, as though and Bothriolepis ornata (Eichwald 1860: pl. 56, found by R. Murchison on Priksha River fig. 3, 1861: pl. 35, fig. 3, Russian edition) and he (Agassiz 1844-1845: 149). However, Andrews inaccurately traced AMD from Helmersen’s (1982), using original drawings for the mono- collection (specimen GM 116/107) without graph, suggested that these specimens were col- mentioning the locality. This bone was later lected by Robertson in Elgin, Scotland, and proposed by Woodward (1891) as a type speci- belong to Bothriolepis gigantea Traquair, 1888, men of B. ornata.

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Lahusen (1880) erected the new species B. pan- shield from the type locality (pl. IV, fig. 15; in deri to commemorate one of the founders of the text erroneously mentioned fig. 12 repro- Russian palaeontology. Unfortunately, he did ducing Nu) now kept in the Naturkunde Museum not chose a type specimen. Pl. 1, figs 1, 2 of in Berlin. He also noted the presence of smaller Lahusen 1880 show the head shield with articu- bones with tubercular ornamentation rather than lated anterior part of the trunk armour (GM with reticular ornament typical for B. cellulosa 1/96) found at Syas’ River near Montsevo by (e.g., Gross 1933: pl. IV, figs 5, 12) from Koknese Pander in 1846. Gross (1932) chose this specimen (Kokenhusen), which were later described as as lectotype of B. panderi. In the pl. 2, figs 2-4, B. tuberculata Gross, 1941. Gross (1933) also Lahusen (1880) reproduced the head shield, analysed the structure of the pectoral fin in various AMD and PMD collected by Trautschold from groups of antiarchs, and proposed a new termi- the other locality at the Syas’ River. Trautschold nology for pectoral fin bones which is still in (1880) also provided a detailed description and use. He also noted for the first time the presence very superficial reproduction of the same head of two new Bothriolepis species in the b-Stufe shield, as well as corrected the shape of Nu and (Amata Formation sandstone in the modern chart). passing of the central sensory line groove in In his fundamental work on the fishes of the Lahusen’s drawings. Later, Jaekel (1927) illus- Baltic Devonian and their stratigraphic signifi- trated this head shield and referred to a new cance, Gross (1942) described Bothriolepis species Bothriolepis traudscholdi. Gross (1933: prima, B. obrutschewi, B. spinosa and B. curonica. pl. 4, fig. 6) indicated the head shield is kept in Due to the political situation in Europe after the Breslau (now Wroclaw in Poland) Museum. Second World War, he was unable to continue Specimens described by Lahusen (1880: pl. 2, this work although a more detailed description figs 2-4) not found neither in Wroclaw, nor in of B. maxima was supplemented by him in St.-Petersburg (A. Ivanov pers. comm.). Stensiö’s monograph (1948). A new period in the study of the Devonian Stensiö (1948) reviewed all known species of vertebrates and especially antiarchs was started Bothriolepis, and proposed the new genus by W. Gross in Latvia and Estonia and Grossilepis for Bothriolepis tuberculata and D. V. Obruchev in Russia. Obruchev (1928) B. spinosa. This classic work provided the most described sclerotic plates of B. panderi, using complete description of the morphology of the lectotype GM 1/96. He improved details of Bothriolepis, using the species B. canadensis, structure of sclerotic plates and provided sup- although some details have since been corrected. plementary arguments in favour of photorecep- Obruchev (1947) provided short definitions of tion as primary function of the pineal organ, as four species of Bothriolepis from Russia and well as homologised the pineal plate of reproduced some bones: PMD of B. cellulosa Bothriolepis with the frontal of osteichthyans. found at Velikaya River near Piskovichi and Gross (1932) published a catalogue of antiarchs, later placed by him in Grossilepis tuberculata provided a full list of references including works (Obruchev 1964: pl. VI, fig. 4); lectotype of on morphology and ecology, a list of antiarch B. panderi; small head shield of B. maxima from species and synonyms, as well as a diagram of Lovat’ River; PMD shown by Gross (1933: their geographical and vertical distribution. pl. IV, fig. 14) and Nu of B. ornata collected by Bothriolepis species from the Main Devonian R. Hecker at Priksha River. Field are represented in the catalogue by four Watson (1961) supplemented details of mor- taxa: Bothriolepis ornata, B. cellulosa, B. panderi phology of Bothriolepis panderi based on an and B. maxima Gross, 1933, which were dealt exceptionaly preserved specimen from Syas’ with in more details by Gross (1933). Since River provided to him by Obruchev. Pander had not selected the type specimen of Karatajūte-Talimaa (1966) provided detailed Pterichthys cellulosa, Gross chose the head- descriptions of Bothriolepis prima Gross, 1942 and

496 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

B. obrutschewi Gross, 1942 including reconstruc- 1986). Some papers were dedicated to the mor- tions of the head-shields and trunk-armours of phology of Bothriolepis (Werdelin & Long 1986; both species. She also described two new Young & Zhang 1992), placoderm phylogeny Bothriolepis taxa without giving specific names. (Janvier & Pan Jiang 1982; Gardiner 1984; Goujet Y. Obrucheva (1974) provided a relatively 1984; Goujet & Young 1995) and ecology of schematic reconstruction of Bothriolepis maxi- ancient animal assemblages including Bothriolepis ma armour based mostly on specimen PIN (Novitskaya et al. 1983; Lukševičs 1992). 1491/41 from Prilovat’ Formation, Lovat’ River, which consists of a nearly complete head shield, dorsal and ventral walls of the trunk armour and DISTRIBUTION AND BIOSTRATIGRAPHY proximal segments of the pectoral fins. For the Ketleri Formation, Lyarskaja & Bothriolepidoids are among the most widely Savvaitova (1974) established two new species, distributed and frequently found vertebrates Bothriolepis ciecere and B. pavariensis from the Main Devonian Field. The genus Lyarskaja, 1974, described on a base of few Bothriolepis is characterised by high diversity imperfectly preserved bones. and comparatively quick evolution, and is Two new species of Bothriolepis from Latvia, important to biostratigraphy, particularly the B. evaldi and B. jani, were described by correlation of Frasnian and Famennian terrige- Lyarskaja (1986) and Lukševičs (1986). Lukševičs nous shallow-water deposits of the Main (1987) provided a more detailed description and Devonian Field of the East European Platform reconstruction of B. curonica Gross, 1942 trunk with strata elsewhere. armour and (Lukševičs 1992) restudied B. orna- One of the earliest reported occurrence of ta type specimen, and collections of Olivieri, Bothriolepis is in the Middle Devonian (Eifelian) Helmersen, Hecker, Talimaa and newly exca- of China (P’an 1981), and in the Aztec Siltstone vated materials and described the type species of (Givetian) of Antarctica (Young 1988). The old- the genus Bothriolepis in more details. est remains of Bothriolepis in the Main Denison’s (1978) review of all known placo- Devonian Field, of probable Givetian age derm fishes listed 46 species of Bothriolepis, two (Gauja Formation), were found in 1964 in bore- species of Grossilepis and Hillsaspis gippslandi- hole material from Latvia (Karatajūte-Talimaa ensis (Hills, 1929), the latter referred back to 1966). Unfortunately these remains are lost. Bothriolepis by Young & Gorter (1981). The precise position of the Middle/Upper Denison (1978) noted various unnamed Devonian boundary on the East European Bothriolepis forms from many countries, and Platform has not been determined as yet (for subsequent descriptions come from Russia discussion see Blieck et al. in press). This (Matukhin et al. 1980; Ivanov & Khozatsky boundary is defined as the base of the lower 1986; Lukševičs & Sorokin 1999), Kazakhstan P. asymmetricus conodont Zone, recognized by (Malinovskaya 1977, 1988, 1992), Iran (Blieck et the first occurrence of Ancyrodella rotundiloba al. 1980), Turkey (Janvier 1983), China (P’an Bryant, 1921. Traditionally the base of the Kiang 1981; Pan Jiang et al. 1980, 1987; Pan Frasnian in the Baltic sequence was placed at the Jiang 1988), Vietnam (Long et al. 1990), North base of the Gauja Regional Stage (Rzhonsnits- America (Virginia) (Weems et al. 1981), kaya & Kulikova 1990). Mark-Kurik (1993) Australia (Long 1983; Long & Werdelin 1986; regarded the Abava, Gauja and Amata Young 1987, 1990; Johanson 1997; Johanson & Formations as Givetian, and placed the base of Young 1999), Antarctica (Young 1988), South the Frasnian at the base of the Pļaviņas Regional Africa (Long et al. 1997), etc. Young published a Stage, i.e. at the base of the Pļaviņas Formation number of works on biogeography, morphology and the Snetnaya Gora Beds (see also Ivanov and phylogeny of placoderms (1974, 1984a, b, 1993).

GEODIVERSITAS • 2001 • 23 (4) 497 Lukševičs E.

TABLE 3. — Distribution of psammosteid, placoderm and acanthodian taxa in the Frasnian of the north-western part of the East European Platform, modified after Ivanov 1990; Ivanov & Khozatski 1986; Lyarskaja & Lukševičs 1992; Esin et al. 2000.

Regional Stages / Beds*

Pļaviņas i Taxa is š ūš Amula Amata Katle Dubnik Stipinai Pam Daugava Gora* Pskov* Snetnaya Chudovo*

Psammolepis undulata (Agassiz, 1844) Plourdosteus livonicus (Eastman, 1896) ? Devononchus concinnus (Gross, 1930) Psammosteus maeandrinus Agassiz, 1844 Psammosteus levis Obruchev, 1965 Psammosteus livonicus Obruchev, 1965 Psammosteus praecursor Obruchev, 1947 ? Psammosteus cuneatus Obruchev, 1965 Psammosteus asper Obruchev, 1965 Karelosteus weberi Obruchev, 1933 Asterolepis radiata Rohon, 1900 Bothriolepis prima Gross, 1942 Bothriolepis obrutschewi Gross, 1942 Plourdosteus mironovi (Obruchev, 1933) Ctenurella pskovensis (Obruchev, 1947) Grossilepis tuberculata (Gross, 1941) Bothriolepis cellulosa (Pander in Keyserling, 1846) Bothriolepis panderi Lahusen, 1880 Haplacanthus perseensis Gross, 1942 “Ptyctodus”sp. Rhynchodus sp. Rhamphodopsis sp. Psammosteus megalopteryx (Trautschold, 1880) Bothriolepis traudscholdi Jaekel, 1927 Asterolepis syasiensis Lyarskaja, 1981 Holonema radiatum Obruchev, 1932 Gyroplacosteus panderi Obruchev, 1932 Plourdosteus trautscholdi (Eastman, 1897) Eastmanosteus egloni (O. Obrucheva, 1956) Psammosteus falcatus Gross, 1942 Psammosteus tenuis Obruchev, 1965 Aspidosteus heckeri Obruchev, 1941 Bothriolepis maxima Gross, 1933 Devononchus laevis (Gross, 1933) Asterolepis? amulensis Lyarskaja, 1981 Bothriolepis evaldi Lyarskaja, 1986 Grossilepis spinosa (Gross, 1942) Taeniolepis speciosa Gross, 1933

A recent study of conodonts from the strato- Formation contains vertebrate assemblages types of the Timan Formation and Ust’ Yarega similar to that of the Pļaviņas Formation Formation in South Timan by Kuzmin (1995) (Ivanov & Lukševičs 1996). This evidence indi- identified the base of the lower P. asymmetri- cates that lower boundary of the Upper cus conodont Zone within the Timan Devonian of the Main Devonian Field should Formation. The upper part of the Timan occurs somewhere between the base of

498 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

TABLE 4. — Distribution of placoderm, acanthodian and sarcopterygian taxa in the Famennian of the north-western part of the East European Platform, modified after Lyarskaya & Lukševičs 1992; Lukševičs 1995; Esin et al. 2000. (Spārnene and Piemare Regional Stages are not officially accepted by the Baltic Stratigraphical Association).

Regional Stages / Formations*

Spārnene Piemare Taxa kis š ri* ere* ervelis* Eleja ū Kursa ķ Ketleri rvete* Akmene Joni agare* M Šķ ē Ž T Sni

Bothriolepis leptocheira Traquair, 1893 Holoptychius cf. nobilissimus Agassiz, 1839 Phyllolepis sp. Bothriolepis heckeri n. sp. Megapomus heckeri Vorobyeva, 1977 Bothriolepis jani Lukševičs, 1986 Bothriolepis ornata Eichwald, 1840 Homacanthus sveteensis Gross, 1942 Phyllolepis tolli Vasiliauskas, 1963 Chelyophorus sp. Dunkleosteus sp. Devononchus tenuispinus (Gross, 1933) Platycephalichthys skuenicus Vorobyeva, 1962 Bothriolepis ciecere Lyarskaja in Lyarskaja & Savvaitova, 1974 Devononchus ketleriensis Gross, 1947 Ventalepis ketleriensis Schultze, 1980 Cryptolepis grossi Vorobyeva, 1975 Glyptopomus bystrowi (Gross, 1941) Orlovichthys cf. limnatis Krupina, 1985 Ventastega curonica Ahlberg, Lukševičs & Lebedev, 1994

Pļaviņas Regional Stage, and the base of the out the Frasnian. There are no psammosteids in Amata Regional Stage. the Famennian deposits, which contain the All studied Bothriolepis material from the Main younger broad assemblage (Fig. 2). Devonian Field comes from the Upper Devonian deposits (Tables 3; 4). There are 15 bothriolepidid taxa known now from the LITHOLOGIES, FACIES VARIATIONS Main Devonian Field (in chronological order): AND VERTEBRATE ASSEMBLAGES Bothriolepis prima, B. obrutschewi, B. cellulosa, B. panderi, B. traudscholdi, B. maxima, B. evaldi, Amata Regional Stage corresponds to the Amata B. leptocheira, B. ornata, B. jani, B. heckeri Formation in Latvia and Estonia (Fig. 3), upper n. sp., Bothriolepis sp. indet. 1, B. ciecere, part of the Šventoji Formation in Lithuania, and Grossilepis tuberculata, G. spinosa. Yam-Tesovo Formation in Russia, which are Two broad assemblages characterised by faunal represented mostly by sandstone and clays, usu- elements associated with the various species of ally without invertebrates. The Pļaviņas Bothriolepis are recognised in the Main Regional Stage of Baltic sequence consists of Devonian Field (see Esin et al. 2000). An older Pļaviņas Formation in Estonia and Latvia, com- assemblage, identified by the presence of psam- prising Jara, Suosa and Kupiškis Beds (or mosteid heterostracan remains, occurs through- Formations: e.g., Narbutas 1994) in Lithuania,

GEODIVERSITAS • 2001 • 23 (4) 499 Lukševičs E.

STANDARD MIO- BALTIC PLACODERM AND HETEROSTRACAN CONODONT SPORE REGIONAL ACANTHODIAN ZONES STAGE

SERIES ZONATION ZONES STAGES ZONES praesulcata Šķervelis Fm expansa SP Ketleri B. cierere barren interval postera Piemare

Spārnene Phyllolepis trachytera B. ornata

FAMENNIAN Akmene marginifera Kursa rhomboidea Im

crepida CZ Joniškis barren interval

triangularis VV Eleja B. leptocheira UPPER

linguiformis DE Amula barren interval

Stipinai

rhenana Pamūšis OG Psammosteus falcatus B. maxima

Katleši FRASNIAN jamieae

Daugava hassi Psammosteus B. trautscholdi SD megalopteryx punctata Dubniki barren interval transitans Pļaviņas B. cellulosa

falsiovalis BI B. prima Devon- Amata B. obrutschewi onchus Asterolepis disparilis IM Gauja ornata concin- hermanni-cristatus Abava* Watsonosteus nus Burtnieki P. tuberculatus MIDDLE varcus GIVETIAN EX Diplacanthus gravis hemiansatus Aruküla P. pauli-P. palaeformis

500 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

and corresponds to the Snetnaya Gora, Pskov tions of vertebrate assemblages, such as abun- and Chudovo Beds in Russia. The deposits cor- dance of psammosteid and asterolepid remains, responding to this stage consist mainly of lime- and rarity of dipnoans in sandy parts of the sec- stones, marls, dolostones and dolomite marls tion could be explained by facial changes with abundant and often diverse remains of (Ivanov 1990). marine invertebrates. The Snetnaya Gora Beds Dubnik Regional Stage of Baltic in the Main deposits (“Cellulosa-Mergel” of Gross 1942; the Devonian Field is represented by sharply varie- Koknese member of Pļaviņas Formation) are gated facies and consists of sandstone-clay, widely distributed all over the Main Devonian limestone-dolomite, clay-carbonate deposits Field from Lithuania to Andoma Hill not far and gypsum, almost everywhere without the from Onega Lake in Russia. These beds contain remains of animals or plants. It comprises the a rich so called “Snetnaya Gora vertebrate Salaspils Formation in Latvia, the Pasvalys Beds assemblage” (Ivanov 1990), which yields about of the Tatula Formation in Lithuania, and 20 fish and agnathan taxa (Table 5). This assem- Dubnik Formation in Estonia and Russia. The blage is represented by three modifications deposits of this age in Baltic contain scarce depending on the facial conditions: so-called remains of undeterminable Bothriolepis Jara, Snetnaya Gora s.s. and Syas’ assemblages. (Sorokin 1978). In the north-eastern part of the The Jara assemblage occurs in western Latvia Main Devonian Field, the gypsum and anhy- and Lithuania, where sandstone, clays and dolo- drite are replaced by sandstone, siltstone, clays stones dominate the sequence, representing sed- and marls. Siltstone, silty marls and clays expo- iments originated in a basin with changeable sured along the Syas’ River, contain a rich salinity of waters varying from lowered to concentrations of vertebrate remains (at least 14 hypersaline, with large input of terrigenous taxa), lingulids, carbonised plants and ichnofos- material. sils (Obruchev & Mark-Kurik 1965; Vorobyeva The Snetnaya Gora s.s. assemblage was first 1977). described by Gross (1933, 1941, 1942); typical Daugava Regional Stage of Baltic corresponds “Cellulosa-Mergel” fauna occurs in central and to the maximum transgression on the territory eastern Latvia, southern Estonia, Pskov region of the Main Devonian Field and contains mostly and southern part of Leningrad region. This carbonate and clayey-carbonate deposits, with assemblage partly extends also in the Pskov thin layers of gypsum and anhydrite in western Beds. Apart form vertebrates the diverse inver- Latvia (Daugava Formation) and Lithuania tebrate fauna evidences gently hypersaline envi- (Kirdonys and Nemunelis Beds of the Tatula ronment with low input of clastic particles. The Formation and the Istras Formation), and with Syas’ assemblage is distributed in north-eastern layers of multicoloured sandstone, siltstone and part of the Main Devonian Field, where terrige- clays in its eastern part (Porkhov, Svinord, nous deposits dominate the sequence (Sorokin Il’men’, Buregi, Altovo Beds) (Sorokin et al. 1978). The differences between the modifica- 1981). The vertebrate remains are very rare and M

FIG. 2. — East Baltic Middle-Upper Devonian Regional Stages, vertebrate zones, and their correlation with the conodont dont and spore zones, modified after Blieck et al. (in press); Ivanov & Lukševičs 1996; Lukševičs 1995; Kleesment & Mark-Kurik 1997; Valiukevičius 1994. *Abava is Regional Substage being not yet accepted as a Regional Stage by the Baltic Devonian Subcommission. The black dots (•) indicate the conodont zones of the previous Standard Conodont Zonation identified in the suc- cession of the Main Devonian Field (Žeiba & Valiukevičius 1972; Valiukevičius 1994; Kuzmin 1996). Miospore zones after Avkhimovitch et al. 1993. Abbreviations: Key to the miospore zones (Z.) and subzones (Subz.): BI, Acanthotriletes bucerus- Archaeozonotriletes variabilis insignis Subz.; CZ, Cyrtospora cristifer-Diaphanospora zadonica Z.; DE, Cristatisporites deliquescens- Verrucosisporites evlanensis Z.; EX, Geminospora extensa Z.; IM, Ancyrospora incisa-Geminospora micromanifesta Subz.; Im, Lagenoisporites immensus Z.; OG, Archaeoperisaccus ovalis-Verrucosisporites grumosus Z.; SD, Geminospora semilucensa- Perotrilites donensis Z.; SP, Spelaeotriletes papulosus Subz.; VV, Corbulispora vimineus-Geminospora vasjamica Z. B., Bothriolepis; P., Pycnosteus.

GEODIVERSITAS • 2001 • 23 (4) 501 Lukševičs E.

FIG. 3. — Stratigraphic charts of the Middle and Upper Devonian of the East Baltic and NW Russia, after Kleesment & Mark-Kurik 1997; Narbutas 1994; Rzhonsnitskaya & Kulikova 1990; Lukševičs, Mūrnieks & Savvaitova 1999; Gailīte et al. 2000 (modified). The names of the stratigraphical units of the north-western Russia here and below follows Rzhonsnitskaya & Kulikova 1990. Abbreviations: B-s, Beds; Mb, Member.

502 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

TABLE 5. — Comparison of modifications of the Snetnaya Gora vertebrate assemblages, modified after Sorokin 1978; Ivanov 1990. *, determination by Sorokin 1978. Abbreviations: A, abundant; R, rare; V, very rare.

Taxa Jara Snetnaya Gora Syas’

P. maeandrinus Agassiz, 1844 A V A P. asper Obruchev, 1965 R Karelosteus weberi Obruchev, 1933 R Asterolepis radiata Rohon, 1900 A V A Bothriolepis cf. obrutschewi * Gross, 1942 R Bothriolepis cellulosa (Pander in Keyserling, 1846) A A Bothriolepis panderi Lahusen, 1880 R Grossilepis tuberculata (Gross, 1941) R A Ctenurella pskovensis (Obruchev, 1947) R V “Ptyctodus” sp. V V Rhynchodus sp. V V Rhamphodopsis sp. V Plourdosteus mironovi (Obruchev, 1933) V A Strunius rolandi (Gross, 1936) A Latvius grewingki (Gross, 1933) A Eusthenopteron saevesoederberghi Jarvik, 1937 R R A Glyptolepis sp. R A Holoptychius sp. A Laccognathus sp. R Rhinodipterus secans (Gross, 1933) R A R Griphognathus minutidens Gross, 1956 R Moythomasia perforata (Gross, 1942) R R R Chondrichthyes indet. V Acanthodii indet. V V

usually poorly preserved in western part of the Vertebrates are absent in the Imula and Bauska Main Devonian Field. Fish remains are practi- Beds of the Stipinai Regional Stage (in western cally absent in the Buregi Member. part of the Main Devonian Field) and are scarce The deposits corresponding to the Katleši in the Smota-Lovat’ Formation (Russia), which Regional Stage in the eastern part of the Main contains no Bothriolepis. The Amula Regional Devonian Field (Snezha Formation in Russia) Stage, corresponding to the Pakruojis Formation are represented mainly by variegated facies and in Lithuania, Amula Formation in Latvia and consists of carbonate clays and siltstone with Kun’ya Beds in Russia, is distributed in Baltic thin layers of sandstone and limestone. In region only in the southern part of western Latvia, this regional stage consists of the Katleši Latvia and north-western Lithuania. It comprises Formation. Several levels of the clays and sands and sandstone with layers of siltstone and dolomite sandstone of the Katleši Formation silty dolostones, which contain the remains of contain a quantitatively rich vertebrate assem- vertebrates in the Lower Amula Member, lin- blages (Sorokin et al. 1981). Pamūšis Regional gulid shells and ichnofossils, changing with Stage comprises the Pamūšis Formation in facially variable clays, clayey siltstone, dolomite Lithuania, Ogre Formation in Latvia and marls and unfossiliferous dolostones (Sorokin Prilovat’ Formation (previous Nadsnezha Beds) et al. 1981). in the eastern part of the Main Devonian Field. The Kruoja and Šiauliai Formations in Lithuania These formations, consisting mainly of sand- and Eleja Formation of Latvia correspond to the stone, clays, marls and dolostones, contain fish Eleja Regional Stage, are suggested to belong to remains in the lower part of sequence, usually the lower Famennian. Deposits of this interval only in sandstone. have no analogues in the eastern part of the

GEODIVERSITAS • 2001 • 23 (4) 503 Lukševičs E.

Main Devonian Field. The lower, Purviņi dolomite marl and siltstone, in sandy deposits Member of the Eleja Formation is composed yields the most diverse fish assemblage of the mostly of clays with thin layers of sandstone, late Famennian age. sometimes of clayey dolostones or dolomite Piemare Regional Stage corresponds to the marls, containing vertebrates. The deposits cor- upper part of the Švete Formation in Lithuania, responding to the Kursa Regional Stage are dis- the Sniķere Formation in Latvia, and the Žagare tributed in the southern part of western Latvia Formation distributed in both countries (Kursa Formation) and north-western Lithuania (Lukševičs, Mūrnieks & Savvaitova 1999). The (Kuršiai Formation) and comprise limestone in Sniķere Formation is characterised by more their western part, with increasing degree of widely represented carbonate deposits, contain- dolomitization and quantity of clastic material ing brachiopods, bivalves, gastropods, crinoids, to the east. The limestone yield a rich and ichnofossils and rare vertebrates. The Švete diverse invertebrate assemblage consisting of Formation contains sandy dolomites, dolomite bryozoans, crinoids, brachiopods, worms, marls and siltstone in upper part. Scarce remains bivalves and gastropods (Sorokin et al. 1981). of brachiopods, bivalves, conodonts and fishes Microremains of acanthodians, sarcopterygians, have been reported from there. The Žagare actinopterygians and recently-found elasmo- Formation is represented mostly by dolostones branchs (Ivanov & Lukševičs 1994), as well as or sandy dolostones with concentrations of bra- macroremains of Phyllolepis Agassiz, 1844 were chiopod shells and crinoids, vertebrate remains recorded from Kursa Formation dolostones, are rare, usually occurring in sandstone with mostly borehole material. Akmene Regional strong dolomite cement. Stage corresponds to the Akmene Formation, Ketleri Regional Stage and the Ketleri which is distributed over a smaller territory than Formation, which is subdivided into three the Kursa Formation in the southern part of members (Lyarskaja & Savvaitova 1974), are western Latvia and north-western Lithuania. distributed in a relatively small territory of The Akmene Formation everywhere shows two south-western part of Latvia and north-western members of dolostones with thin layers of sand- part of Lithuania, comprising sands, sandstone, stone, siltstone and clays (Sorokin et al. 1981). clays and dolomite marls. The lower, Nigrande The dolostones contain a diverse assemblage of Member contains mostly clayey-carbonate marine invertebrates, such as brachiopods, deposits, which contain fragments of poorly bivalves, bryozoans, crinoids and worms, as preserved fishes. The middle and upper, Pavāri well as the remains of fishes. Fish remains from and Varkaļi members consist of light-coloured the Bilovo Beds, which are usually interpreted unconsolidated sandstone, more hard sand- as corresponding to the Akmene Formation, are stone, siltstone, clays and dolomite marls poorly known, but contain the remains of a new (Lyarskaja & Savvaitova 1974; Lukševičs 1991). species, Bothriolepis heckeri n. sp. Spārnene Both members are characterised by a diverse Regional Stage corresponds to the Mūri fish and primitive tetrapod assemblage Formation, occurring in Latvia and Lithuania, (Lukševičs 1991; Ahlberg et al. 1994; Lebedev the Tērvete Formation of Latvia, and lower part 1995). of the Švete Formation of Lithuania (Lukševičs, The last version of the vertebrate zonation based Mūrnieks & Savvaitova 1999). The sandstone, on the stratigraphic ranges of Bothriolepis have sand and carbonate sandstone with thin layers been recently proposed for the mostly shallow- of coquinas of the Mūri Formation usually con- water facies, rich in terrigenous deposits, of the tain well-preserved shells of brachiopods, Main Devonian Field (Ivanov & Lukševičs 1996; bivalves, gastropods, nautiloids, crinoid remains Esin et al. 2000). The complete zonation (Fig. 2) and vertebrates. The Tērvete Formation, com- consists of four biozones for the Frasnian: prising almost unconsolidated sandstone, B. prima-B. obrutschewi zone, corresponding to

504 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

the Amata Regional Stage; B. cellulosa zone DIAGNOSIS. — Bothriolepididae in which the AMD (Snetnaya Gora and Pskov Beds of the Pļaviņas plate is broadest across its lateral corners, and normally overlaps the ADL and is overlapped by the MxL Regional Stage); B. traudscholdi zone (Dubnik plate. The MxL plate is broadest through its dorsal and Daugava Regional Stages); B. maxima zone corner, with its lateral lamina of similar extent to the (Snezha and Pamūšis Regional Stages); and three lateral lamina of the ADL plate, and not forming zones with one subzone for the Famennian: extensive contact with the AVL plate. B. leptocheira zone (Eleja Regional Stage); Phyllolepis zone (from the Kursa to the Bothriolepis prima Gross, 1942 Spārnene Regional Stage); B. ornata subzone (Figs 4-6) (Spārnene Regional Stage); B. ciecere zone (the Bothriolepis prima Gross, 1942: 415, 416, abb. 6A. Pavāri and Varkaļi members of the Ketleri Formation). There are several intervals in the HOLOTYPE. — AMD, Riksmuseet, Stockholm. Upper Devonian section possessing scarce ver- MATERIAL EXAMINED. — Disarticulated plates (LGI tebrate remains, therefore it is impossible to 5/1064, 1066, 1072-1074, 1080, 1089, 1215, 2202-2204, 2243, 2245-2247, 2253, 2254, 2264-2270, 2272, 2273, establish vertebrate zones for such intervals as 2286, 2295-2299, 2301, 2302, 2304, 2305, 2307-2311, the Chudovo Beds, the Stipinai, Amula, 2322, 2323, 2325-2327, 2341, 2342, 2383, 2385, 2388, Joniškis, and Piemare regional stages, as well as 2398-2406, 2410-2412, 2699-2703). Fragments of the the uppermost part of the Baltic Devonian sec- trunk-shield and pectoral fin bones (LDM 43/584) are Šķ specimens additional to the material described by tion comprising the ervelis Formation. Karatajūte-Talimaa (1966) from Pastamuiža locality. This vertebrate zonation is useful not only in LOCALITIES AND HORIZON. — Daugava River near the Main Devonian Field, but also in adjacent Pastamuiža in the vicinity of Koknese (Kokenhusen), territories, for example in Timan province, Latvia; Upper Devonian, lower Frasnian, upper part where the most part of the Frasnian zones could of the Amata Formation. Pelyša River, Lithuania; Š be traced and correlated with the standard con- uppermost part of the ventoji Formation. Yam- š č Tesovo at Oredezh River, Leningrad region of odont zonation (Ivanov & Luk evi s 1996), and Russia; Staritsa Beds of the Yam-Tesovo Formation. Severnaya Zemlya (Lukševičs 1999a). DIAGNOSIS. — Small Bothriolepis with a median dorsal armour length reaching 50 mm. B/L index of the head-shield of 140-150. Weakly convex rostral margin SYSTEMATICS slightly shorter than the posterior margin; obtected nuchal area present only on Nu. Orbital fenestra is relatively large. Nu bears posterior process. Dorsal Order EUANTIARCHA Janvier & Pan, 1982 wall of trunk-armour broad and high in its anterior Suborder BOTHRIOLEPIDOIDEI Cope, part and relatively narrow in posterior part, B/L 1886 index 77. Lateral wall is high. Tergal angle and median dorsal ridge are weakly defined. Postlevator cristae on the visceral surface of AMD are straight and enclosing Family BOTHRIOLEPIDIDAE Cope, 1886 a relatively sharp angle. AMD relatively broad, arched, B/L index of 99. Dorsal lamina of ADL rela- DIAGNOSIS. — Bothriolepidoids with a small Pp sepa- tively narrow, dorsal and lateral laminae enclosing an rated from the La by the Nu, which forms part of the angle about 122-128°. Angle between the dorsal and posterior margin of the orbital fenestra. AMD with a lateral walls on MxL is sharper: about 112°. Lateral broad anterior margin; processus obstans strongly and ventral walls enclosing an angle about 109° on developed; PDL and PL replaced by a single MxL; PVL. Dorso-lateral ridge is weakly defined in its ante- semilunar plate unpaired. Adducted pectoral rior part and is very well-developed in the posterior appendage reaching back beyond trunk shield; central part of the trunk-shield. Ventro-lateral ridges are dorsal plate 2 small, and separated from central dorsal strongly developed. Lateral lamina of PVL is 1.7 time plate 1 by lateral and mesial marginal plates 2. as long as it is high. Ventral wall of the trunk-shield is relatively narrow, B/L index of 46, with relatively broad anterior part and narrow posterior part. Lateral Genus Bothriolepis Eichwald, 1840 and mesial spines on the proximal segment are separate and relatively long. Ornamentation reticulate in TYPE SPECIES. — Bothriolepis ornata Eichwald, 1840, small and moderately large individuals, tuberculate in subsequently designated by Woodward (1891).

GEODIVERSITAS • 2001 • 23 (4) 505 Lukševičs E.

A C

FIG. 4. — Bothriolepis prima Gross, 1942; A, incomplete head-shield LGI 5-2202; B, incomplete head-shield LGI 5-2203; C-E, restored trunk armour, based on the right ADL LGI 5-2699, MxL LGI 5-2700, AVL LGI 5-2701, right PVL LGI 5-2702 and left PVL LGI 5-2703 in lateral, dorsal and ventral views (produced by V. Talimaa). Daugava River near Pastamuiža, Latvia. Amata Formation. Abbreviations: ADL, anterior dorso-lateral plate; AVL, anterior ventro-lateral plate; MxL, mixilateral plate; PVL, posterior ventro-lateral plate. Scale bar: 10 mm. large individuals. Central part of the dorsal and ven- fenestra is large, but relatively narrow. Such tral walls is almost smooth. Pit-line groove crossing proportions of orbital fenestra in antiarch fishes the dorso-lateral ridge on the MxL is always present. is typical for young individuals (Long & Werdelin 1986; Upeniece & Upenieks 1992). DESCRIPTION The Prm is moderately broad and short, it is As noted by Karatajūte-Talimaa (1966), the broadest at the antero-lateral corners of the head-shield (Figs 4A, B; 5) is strongly vaulted plate. The rostral margin is slightly convex. The and broad. The antero-lateral corners (alc) and orbital margin is concave in specimen LGI the prelateral notch (nprl) are gently defined. 5/1064 from Pelyša River, it is only slightly The obtected nuchal area (nm) is relatively shorter than the rostral margin (Karatajūte- broad, well-defined only on the Nu. The orbital Talimaa 1966). The infraorbital sensory groove

506 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

A (csl) finishes at the level of middle of the orbital margin of the orbital fenestra. The Pp is broad in small individuals and of moderate breadth in csl1 maturity. Its anterior margin is convex in both csl small and larger specimens. The Nu is relatively broad with a L/B index 68- 70 (n = 3). The plate is usually broadest across the lateral corners, but in specimen LGI 5/2402 it is broadest across the postero-lateral corners. The anterior division of the lateral margin usual- soc ifc1 ly is straight and a little shorter than the strong- B ly concave posterior division. The anterior ifc2 margin with the deep and broad postpineal Prm notch (Karatajūte-Talimaa 1966). The posterior La cir margin is usually almost straight or slightly csl concave. The central sensory line groove is clearly distinct. The outer openings of the Pp endolymphatic ducts are small but clearly defined, lying not far from the obtected nuchal area. Nu Pn Pmg The Pn is of moderate breadth, L/B index is 74 mp and 83 in two measured specimens. The plate d.end bears clearly seen middle pit-line groove (Karatajūte-Talimaa 1966). FIG. 5. — The head-shields of Bothriolepis prima Gross, 1942, reconstructed by Karatajūte-Talimaa (1966: fig. 1); A, based on The Pmg is broad with the lateral margin slight- the head-shield LGI 5-2202; B, based on the head-shield LGI 5- ly longer than the median margin (Karatajūte- 2203. Daugava River near Pastamuiža, Latvia. Amata Formation. Abbreviations: La, lateral plate; Nu, nuchal plate; Pmg, post- Talimaa 1966). marginal plate; Pn, paranuchal plate; Pp, postpineal plate; Prm, The trunk-armour (Figs 4C-E; 6) is relatively premedian plate; cir, semicircular pit-line groove; csl, central sensory line groove; csl1, additional branchs of central sensory narrow as restored by Karatajūte-Talimaa (1966: line groove; d.end, opening of canal for endolymphatic duct; figs 3, 4), with broader anterior part of the dor- ifc1, principal section of infraorbital sensory line; ifc2, branch of infraorbital sensory line diverging on La; mp, middle pit-line sal and ventral walls of the trunk-armour and groove; soc, anterior section of the supraorbital sensory line. much narrower posterior part of that walls, Scale bar: 10 mm. hence broad subcephalic division and narrow and relatively high apperture for the tail. crosses the plate in its anterior part, but not so Karatajūte-Talimaa suggested that this fish had close to the rostral margin as in B. obrutschewi narrower and shorter tail than the other repre- (pers. obs.). sentatives of the genus Bothriolepis. The length The La, Pp and Nu were not described by of the dorsal wall reaches about 60 mm. The Karatajūte-Talimaa (1966) in details. The La is dorso-lateral and ventro-lateral ridges are well- moderately broad with the L/B index 140-144, marked, especially the ventro-lateral ridge and 142 on the average (n = 4). It is narrow in the the posterior part of the dorso-lateral ridge. The anterior part and broad in the posterior part. median dorsal ridge is weakly defined, and is The rostral margin is relatively short and almost usually better developed posteriorly, on the straight, the antero-median margin is short. The PMD. The angle enclosed by the dorsal and lat- infraorbital sensory line groove crosses the plate eral walls is obtuse in the anterior part of the in its anterior part not far from the rostral and trunk-armour (measured on the ADL: 122- lateral margins. The central sensory line groove 128°), and is more sharp in the posterior part

GEODIVERSITAS • 2001 • 23 (4) 507 Lukševičs E.

AB AMD PMD AMD ADL

dlg2 dlr ADL dxp

lcg

MxL PVL vlr AVL f.ax p.br C SM dxp AVL

PMD p.br

PVL

FIG. 6. — Reconstruction of the trunk armour of Bothriolepis prima Gross, 1942; A, dorsal view; B, lateral view; C, ventral view (from Karatajūte-Talimaa 1966: fig. 3). Abbreviations: ADL, anterior dorso-lateral plate; AMD, anterior median dorsal plate; AVL, anterior ventro-lateral plate; MV, median ventral plate; MxL, mixilateral plate; PMD, posterior median dorsal plate; PVL, posterior ventro-lateral plate; SM, semilunar plate; dlg2, posterior oblique dorsal sensory line groove; dlr, dorso-lateral ridge of trunk armour; dxp, dorso-ventral pit-line groove; f.ax, axillary foramen; lcg, main lateral line groove; p.br, processus brachialis; vlr, ventro-lateral ridge of trunk armour. Scale bar: 10 mm.

(on the MxL: 112° on the average). The angle antero-lateral and lateral corners are well- enclosed by the lateral and ventral walls is about defined, but the postlevator processes are weak- 109° (all angle measurements follow Karatajūte- ly developed. The posterior division of the Talimaa 1966). lateral margin is only 1.2-1.9 time shorter than The AMD is relatively broad, B/L index is 92 the anterior division (Karatajūte-Talimaa and 105 in two measured specimens, characteris- claimed that this feature is rather variable and ing by a variable shape. As noted by Karatajūte- reaches 1.13-3.22 in B. prima, but I did not Talimaa (1966), the anterior margin is broad, find the specimens with such an extremely weakly convex, posterior margin short, 1.2- long anterior division of the plate among the 1.8 time shorter than the anterior margin. The material). The median dorsal ridge and the tergal

508 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

angle (dma) are weakly marked. Overlap areas angle between laminae, and sutural connections for the MxL are normally developed as usually of the plate. The dorsal lamina of the plate is 1.4- in Bothriolepis; only in one case for 48 over- 1.7 time as long as it is broad, 1.57 on the average, looked by Karatajūte-Talimaa (1966), in LGI and possesses a well-defined relatively sharp 5/2247, the AMD overlaps the MxL by its ante- dorsal corner. The lateral lamina is relatively rior part of the posterior division of the lateral low, the dorsal length of the plate 2.8-4.1 times margin similar as in Remigolepis. The anterior (3.6 on the average) exceeds the height of the lat- (dlg1) oblique dorsal sensory line grooves are eral lamina. The posterior oblique sensory line weakly defined only on the plates of individuals groove (dlg2) terminates close to the lateral mar- of small size: LGI 5/2247 and 5/1066 with the gin, in some distance from the dorso-ventral pit- length of the AMD 13 and 17 mm respectively line groove (dxp) crossing the dorso-lateral (pers. obs.). The posterior (dlg2) oblique dorsal ridge, similarly to B. obrutschewi, but in speci- sensory line grooves usually are well-defined. men LGI 5/1072 both grooves are connected The visceral surface of the AMD shows a slight- with each other. The overlap area for the AMD ly lengthened triangular-shaped levator fossa is usually as normally in Bothriolepis, only in (f.retr), which is limited by the low postlevator one case (LGI 5/2403) it is restricted to approxi- thickenings (alr) without the postlevator cristae mately one fourth of the length of the antero- (Karatajūte-Talimaa 1966), as it is seen in the dorsal margin (Karatajūte-Talimaa 1966), as in specimens from Yam-Tesovo, or probably in a Remigolepis (Stensiö, 1931). posterior part also by the postlevator cristae, as The AVL is relatively broad in subcephalic divi- it was figured by Gross (1942: abb. 6A). sion (Karatajūte-Talimaa 1966), the ventral lam- The PMD is relatively narrow, B/L index is 75 ina is 1.5-1.6 time (n = 3) as long as it is broad. and 86 in two measured specimens. The poste- The subcephalic division is extremely short and rior margin is usually strongly convex, but comprises only about 15% of total length of the rounded, without pronounced posterior corner ventral lamina. The antero-lateral corner is situ- (Karatajūte-Talimaa 1966). The width of the ated slightly medially the axis of the ventro- anterior margin varies between 46-56% of lateral ridge. The ventral lamina is 2.6-3 times as total breadth, being almost of the same pro- broad as the low lateral lamina high. The axillary portions as that of B. obrutschewi. The lateral foramen (f.ax) is relatively large and rounded or corners are well-defined, the postero-lateral gently elongated in shape (4.1 × 3.6 mm in LGI corners are often rounded. The median dorsal 5/2701 with total length of the ventral lamina ridge is usually present only in the posterior reaching 33.3 mm). half of the plate in well-grown individuals The PVL is relatively broader than that in (pers. obs.). B. obrutschewi: the ventral lamina is 2.0- The ADL is moderately broad, the dorsal lami- 2.3 times as long as it is broad. The subanal na is 2-2.3 time as long as it is broad and its division occupies about one fourth or fifth breadth 1.1-1.2 time exceeds height of the lateral (17-26%) of the total PVL length. The lateral lamina. The dorso-lateral ridge (dlr) is better lamina is high, the ventral lamina is 1.1-1.5 defined in the posterior part of the ADL (1.28 on the average) time as broad as the (Karatajūte-Talimaa 1966). Dorsal and lateral lateral lamina high. The angle between laminae laminae of the plate enclosing an angle of is more steep as in B. obrutschewi and reaches about 124° on the average (Karatajūte-Talimaa about 109° (Karatajūte-Talimaa 1966). The left 1966), which is more obtuse than that in PVL overlaps the right one by a wide overlap- B. obrutschewi. The processus obstans is ping area (Karatajūte-Talimaa 1966). The strongly developed (Karatajūte-Talimaa 1966). ventro-lateral ridge (vlr) is clearly defined, The MxL was not described by Karatajūte- sometimes slightly pronounced over the lateral Talimaa (1966) in details except the proportions, lamina.

GEODIVERSITAS • 2001 • 23 (4) 509 Lukševičs E.

The MV is typically developed: it is relatively are several tubercular ridges parallel to the small and of rhombic shape (Karatajūte-Talimaa posterior margin on the subanal division of 1966). the PVL. The pectoral fin is represented by several disarticulated bones, and three specimens showing REMARKS articulated plates of the proximal segment. The following account is the first full treatment Karatajūte-Talimaa (1966) claimed that the L/B in English, which supplements Karatajūte- index of the proximal segment is 3.8-4.5, but I Talimaa’s (1966) good description (in Russian) found it to be more elongated being 4-4.6 times of Bothriolepis prima, adding some details of as long as it is broad. The CV1 is making contact structure. It is based mainly on the collections of with the MM2. The distal segment is much Karatajūte-Talimaa’s and Lyarskaja. shorter than that in B. obrutschewi, it is 3.8 times as long as it is broad (Karatajūte- DISCUSSION Talimaa 1966). It shows no traces of an individ- Bothriolepis prima resembles B. obrutschewi and ual plates. Probably, Karatajūte-Talimaa (1966) B. evaldi from the Main Devonian field, and correctly suggested that the pectoral fin does B. hydrophila (Agassiz, 1844) (Miles 1968) from not extend posteriorly far from the posterior Scotland. For differences with B. obrutschewi margin of the trunk-armour ventral wall. The and B. evaldi, see the descriptions below. CD1 is relatively short and broad with L/B B. prima differs from B. hydrophila in 1) smaller index varying from 2.7 to 2.9 (2.8 on the aver- size; 2) broader dorsal wall of the trunk-shield; age). The CV1 is slightly longer than the CD1. 3) shape and proportions of the AMD; 4) nar- The ML2 is elongated, proportionally much rower ventral wall of the trunk-shield; 5) shorter longer than that in B. obrutschewi, it is 4.8- proximal segment of the pectoral fin. B. prima 5.1 times as long as it is broad measured from can be distinguished from B. cellulosa (see Gross the dorsal side, and 4.1-4.7 times as long as it is 1941), other lower Frasnian Bothriolepis repre- broad measured from the ventral side. Both seg- sentative from the Main Devonian Field mostly ments bear prominent lateral and mesial spines. by 1) its much smaller size; 2) narrower lateral The well-defined mesial edge of the proximal division of the Pn; 3) proportions of the trunk- segment bears isolated mesial spines and the lat- armour; 4) narrower PMD; 5) relatively narrow- eral spines are fused in their base forming well- er proximal segment of the pectoral fin; 6) CV1, defined crest (Karatajūte-Talimaa 1966). which is making contact with the MM2; The ornamentation was well described by 7) smooth median part of the dorsal wall of the Karatajūte-Talimaa (1966), it is typically reticu- trunk armour. Small Bothriolepis remains of late, in small and medium-sized individuals of a similar size from Kazakhstan (Malinovskaya fairly regular fine-meshed network of well- 1977, 1988) are too incompletely described and defined anastomosing ridges, becoming almost figured to make the detailed comparisons. smooth in the middle part of the dorsal wall of the trunk-armour, including the posterior part Bothriolepis obrutschewi Gross, 1942 of the AMD, the anterior part of the PMD, the (Figs 7-10) postero-median part of the ADL, and the Bothriolepis obrutschewi Gross, 1942: 416-418, antero-median part of the MxL, as well as on the abb. 7B. median part of the ventral wall. In rather large individuals ornamentation of the head-shield HOLOTYPE. — MxL Riksmuseet, Stockholm. and dorsal wall of the trunk-armour become MATERIAL EXAMINED. — LGI 5/2248, complete head- more tuberculate. The ornamentation on the shield with articulated anterior part of the trunk armour and proximal segments of the pectoral fin; subcephalic division of the AVL consists of 5/2249, articulated ventral wall of the trunk armour oblique tubercular ridges, and sometimes there with proximal segments of the pectoral fin and head-

510 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

A, C-E

FIG. 7. — Bothriolepis obrutschewi Gross, 1942; A, head-shield and AMD, probably belonging to the same individual LGI 5-2345; B, head-shield of small individual LGI 5-2255; C, D, head-shield LDM 43/1004, in visceral and dorsal views; E, PMD LDM 43/635. Daugava River near Pastamuiža, Latvia. Amata Formation. Abbreviations: AMD, anterior median dorsal plate; PMD, posterior median dorsal plate. Scale bars: 10 mm. shield in visceral view; 5/2255, 2345, 2598, 2647, artic- 1101, AMD from Pelyša locality. LGI 5/1216-1222, ulated head-shields; 5/2213-2235, 2238-2241, 2243, disarticulated plates of the armour; Paroveja bore- 2247, 2250-2252, 2255-2260, 2262, 2263, 2274-2284, hole. All this material collected by V. Karatajūte- 2288, 2320-2325, 2341-2345, 2350-2354, 2356-2382, Talimaa and L. Lyarskaja. LDM 307/1-10, AMD, 2416-2445, 2447-2450, 2452-2457, 2459-2482, 2484, PMD, ADL, 2 MxL, Nu, 3 CD1 from Pērse locality, 2485, 2487-2491, 2498, 2500-2531, 2533-2539, 2552, samples gathered and presented to LDM by amateur 2560-2582, 2584-2601, 2603-2615, 2622-2647, 2652- collector Jānis Blesse. 2656, 2659-2661, 2664-2669, 2672, 2674-2683, 2685, LOCALITIES AND HORIZON. — Pastamuiža locality on 2687-2689, 2697, 2698, LDM 43/1004, articulated the right bank of Daugava River; outcrop on the Pērse head shield; 43/585-671, 43/722: disarticulated plates River near Koknese close to the type locality, expo- of the armour from Pastamuiža locality. LGI 5/1099- sure on the left bank of Daugava River near Zvirgzdi,

GEODIVERSITAS • 2001 • 23 (4) 511 Lukševičs E.

straight, without nasal notches. Rostral margin of A Prm weakly convex. Anterior and posterior margins of orbital fenestra straight, lateral division of Pn nar- csl1 row, and Pmg elongated. Dorsal wall of trunk- csl armour low and relatively narrow (B/L index 86), tergal angle weakly defined, and situated in anterior part of middle third of AMD. Median dorsal ridge on AMD present only in very small individuals, and more clearly defined in PMD. AMD B/L index about 94. Anterior division of the lateral margin is more than twice as long as the posterior division. Overlap area for MxL often of Remigolepis-type. PMD B/L index about 91. Dorsal and lateral laminae of ADL soc enclosing an angle of about 121°. Angle between the dorsal and lateral walls on MxL about 114°. Lateral and ventral walls enclosing an angle about 119° on B ifc2 PVL. Lateral lamina of PVL is relatively high with well-defined dorsal corner. MV is small. Proximal segment of the pectoral appendage of moderate csl ifc1 length, 3.8-4.5 times as long as it is broad. Distal segment is relatively long and narrow, 5-5.4 times as long as it is broad. Mesial spines on the proximal segment, as well as dorsal and ventral spines on the distal segment are well-defined, separate and relatively long. Lateral spines on the proximal segment are long and fused in their base forming well-defined ridge. mp Ornamentation is always reticulate on the ventral wall. Ornamentation of the head-shield and dorsal FIG. 8. — The head-shields of Bothriolepis obrutschewi Gross, wall of the trunk-armour, as well as dorsal surface of 1942; A, head-shield of small individual LGI 5-2255; B, head- the proximal segment is tuberculate, which is not shield of well-grown individual LGI 5-2345. From Karatajūte- always well-defined. Talimaa 1966: figs 6, 1, 2. Daugava River near Pastamuiža, Latvia. Amata Formation. Abbreviations: csl, central sensory line groove; csl1, additional branchs of central sensory line groove; ifc1, principal section of infraorbital sensory line; ifc2, branch of DESCRIPTION infraorbital sensory line diverging on La; La, lateral plate; The head-shield in small individuals (Figs 7B; mp, middle pit-line groove; soc, anterior section of the supraorbital sensory line. Scale bars: A, 5 mm; B, 10 mm. 8A) has a large orbital fenestra and short anteri- or division (Karatajūte-Talimaa 1966). In larger individuals (Figs 7A, C, D; 8B), the head-shield Latvia; Upper Devonian, lower Frasnian, upper part is moderately broad with B/L index about vary- of the Amata Formation. Pelyša River; Paroveja bore- ing from 123 to 131. In general, the head-shield hole, 49.65-49.75 m deep, Lithuania; uppermost part of B. obrutschewi is narrower than that of B. cel- Š of the ventoji Formation. Piskovichi and Yam- lulosa and B. prima (Karatajūte-Talimaa 1966). Tesovo, Russia; Podsnetnaya Gora Member of the Yam-Tesovo Formation. Out of the Main Devonian She shown the rostral margin of the head-shield Field this species have been reported (Ivanov & sometimes bearing the rostral angle, almost Lukševičs 1996) from the Middle Timan, Uste Chirka straight posterior margin, gently defined antero- Formation and lowermost Uste Srednyaya Beds of lateral corners (alc) and prelateral notch (nprl). the Uste Yarega Formation; and with slight doubt ū from the North Timan, Kumushka Formation. Karataj te-Talimaa (1966) noted that the Probably, the same species occurs in lower part of the obtected nuchal area (nm) is relatively broad, Matusevich Formation of Severnaya Zemlya well-defined only on the Nu, but I found that in š č (Luk evi s 1999). some cases it extends also into Pn. The shape of DIAGNOSIS. — Bothriolepis of moderate size with a the preorbital recess was not clearly shown by median dorsal armour length reaching 80-85 mm. B/L Karatajūte-Talimaa (1966); it is well seen in a index of the head-shield 127. Preorbital recess of simple type. Weakly convex rostral margin slightly short- newly prepared specimen LDM 43/1004 being er than the posterior margin. Orbital margin of Prm is of simple type.

512 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

FIG. 9. — Bothriolepis obrutschewi Gross, 1942, trunk armour, based on the AMD LGI 5-2632, PMD LGI 5-2561, right ADL LGI 5- 2377, left ADL LGI 5-2363, left MxL LGI 5-2498, right AVL LGI 5-2504, left AVL LGI 5-2511, left PVL LGI 5-2252 in lateral, ventral and dorsal views (plasticine reconstruction produced by V. Talimaa). Daugava River near Pastamuiža, Latvia. Amata Formation. Abbreviations: ADL, anterior dorso-lateral plate; AMD, anterior median dorsal plate; AVL, anterior ventro-lateral plate; MxL, mixilateral plate; PMD, posterior median dorsal plate; PVL, posterior ventro-lateral plate. Scale bar: 10 mm.

The Prm is moderately broad, the B/L index Prm. The rostral angle (ac) is present only changing from about 134 in smallest individ- on the two large Prm. The orbital margin ual with the Prm 6 mm long to 94-95 in is 1.4-1.8 time shorter than the rostral well-grown individuals with 16-18 mm long margin.

GEODIVERSITAS • 2001 • 23 (4) 513 Lukševičs E.

A B AMD PMD

dlg2 ADL MxL AMD ADL dxp lcg dlg2

AVL PVL MxL p.br f.ax

dxp dmr SM PMD p.br

C f.ax AVL

ADL

vlr MxL PVL

FIG. 10. — The trunk armour of Bothriolepis obrutschewi Gross, 1942 reconstructed by Karatajūte-Talimaa (1966: fig. 10); A, dorsal view; B, lateral view; C, ventral view. Daugava River near Pastamuiža, Latvia. Amata Formation. Abbreviations: ADL, anterior dorso- lateral plate; AMD, anterior median dorsal plate; AVL, anterior ventro-lateral plate; MV, median ventral plate; MxL, mixilateral plate; PMD, posterior median dorsal plate; PVL, posterior ventro-lateral plate; SM, semilunar plate; dlg2, posterior oblique dorsal sensory line groove; dlr, dorso-lateral ridge of trunk armour; dmr, dorsal median ridge of trunk armour; dxp, dorso-ventral pit-line groove; f.ax, axillary foramen; lcg, main lateral line groove; p.br, processus brachialis; vlr, ventro-lateral ridge of trunk armour. Scale bar: 10 mm.

The La is moderately broad with the L/B index sion (pr.po) extending forward slightly over the 130-173, 148 on the average. The rostral margin middle of the orbital fenestra. The transverse is almost straight, the antero-median and antero- lateral groove (tlg) is broad and clearly defined. lateral corners are well-defined (Karatajūte- The lateral pit (p) is broad, shallow and situated Talimaa 1966). The infraorbital sensory line equally spaced from an orbital edge of the La groove crosses the plate in its anterior part not and prelateral notch. far from the rostral and lateral margins. The cen- The Nu is relatively broad with a L/B index 57- tral sensory line groove (csl) usually finishes at 74, 66 on the average. The plate is usually broad- the level of the orbital margin of the orbital fen- est across the lateral corners. The anterior estra. The visceral plate surface shows the division of the lateral margin usually is straight antero-lateral corner of otico-occipital depres- and a little shorter than the strongly concave

514 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

posterior division. The posterior margin is usu- (1966). The anterior part of the plate is weakly ally almost straight, but in LGI 5/2654 it is arched, the posterior part is flattened. The ante- strongly concave. It always bears the median rior margin may be weakly convex or less often posterior process (mppr). The central sensory fairly straight. It is relatively narrow. The line groove is clearly distinct. antero-lateral and lateral corners, as well as the The Pn is of moderate breadth, L/B index about postlevator processes are well-defined. The pos- 74-97, 84 on the average. As it was stressed by terior division of the lateral margin is 1.5- Karatajūte-Talimaa (1966), the lateral division of 2.3 times shorter than the relatively long the Pn in B. obrutschewi is comparatively nar- anterior division. The median dorsal ridge is rower than that in B. prima, B. panderi and weakly defined as a longitudinal row of fused especially B. cellulosa and comprises 42-55% tubercles. Overlap areas for the MxL are nor- (48% on the average) of the general breadth of a mally developed as usually in Bothriolepis, but plate. The median division of the plate is broad. in LGI 5/2215, 5/2639, 5/2697, the AMD over- The Pmg is moderately broad with the lateral laps the MxL by its anterior part of the posterior margin slightly longer than the median margin division of the lateral margin similar as in (Karatajūte-Talimaa 1966). Remigolepis. There are some cases the ADL The Sm (extralateral) plate is known from one overlaps the AMD in the posterior portion of specimen, LGI 5/2230 (Karatajūte-Talimaa the common suture: LGI 5/2639, LDM 43/656. 1966: pl. IX, fig. 12). It is relatively long with a The anterior (dlg1) oblique dorsal sensory line L/B index of about 250. The dorsal margin has a grooves are well-defined only on the plates of prominent antero-dorsal process and narrow individuals of small size: LGI 5/2251 and 5/2252 posterior attachment area for the skull. The pos- with the length of the AMD 13 and 18.4 mm terior margin is strongly convex, the ventral respectively. The posterior (dlg2) oblique dorsal margin is weakly convex. The well-marked lat- sensory line grooves usually are well-defined. In eral notch is rather deep separating the plate into some cases the posterior oblique dorsal sensory a short thick anterior division and more thin line grooves are shortened or interrupted (LGI posterior division. There is a groove running 5/2639), in one specimen (LDM 307/1) there are along the dorsal margin of the ornamented part two parallel branches of this groove on the left of the plate, which is similar to that of side of the plate (pers. observation). B. macphersoni Young, 1988. It has the charac- The visceral surface of the AMD shows a slight- ter of a sensory groove. ly lengthened triangular-shaped levator fossa, The trunk-armour (Figs 9; 10) is moderately which is limited by the low postlevator thicken- broad as it was reconstructed by Karatajūte- ings and in a posterior part also by the postleva- Talimaa (1966), weakly arched anteriorly and tor cristae. The anterior ventral pit and the more arched posteriorly with B/L index 86. The median ventral ridge are well-defined. length of the dorsal wall, probably, is more than The PMD (Fig. 7E) is moderately broad, B/L 110 mm. The ventral wall is not quite flat, but index about 82-101, 91 on the average. The pos- slightly arched in rostrocaudal direction. The terior margin is usually strongly convex, with subcephalic division of the ventral wall is rela- pronounced posterior corner, but there are tively narrow and short. The subanal division of specimens with rounded posterior corner moderate length. The median dorsal ridge is noticed. The width of the anterior margin varies weakly defined, in well-grown individuals it is between 48-57% of total breadth, it is relatively developed only on the PMD. The dorso-lateral broader than that of B. prima, but narrower and ventro-lateral ridges are well-marked. than that of B. cellulosa (Karatajūte-Talimaa The AMD (Fig. 7A) is moderately broad, B/L 1966). The lateral corners are well-defined, index about 89-98, 94 on the average. This plate the postero-lateral corners are often rounded. was well described by Karatajūte-Talimaa The median dorsal ridge is present only in the

GEODIVERSITAS • 2001 • 23 (4) 515 Lukševičs E.

posterior half of the plate in well-grown indi- less a sharp angle between cit1 and cit2, unlike as viduals (Karatajūte-Talimaa 1966). The median in B. ciecere or B. karawaka Young, 1988 is ventral ridge and median ventral groove with clearly seen. short posterior ventral pit (pt2) are well-defined The PVL has similar proportions to the AVL, as on the visceral surface of the plate. The crista in most Bothriolepis species. It is of moderate transversalis interna posterior (cr.tp) is normally breadth, the ventral lamina is 2.1-2.6 times as developed, the postmarginal area (pma) is rather long as it is broad. The subanal division is rela- broad. tively broad (Karatajūte-Talimaa 1966), it occu- The ADL is relatively broad, the dorsal lamina pies about one forth (23-28%) of the total PVL is 1.9-2.1 times (2.4-2.5 by Karatajūte-Talimaa plate length. The lateral lamina is moderately 1966) as long as it is broad and its breadth 1.2- high, it is relatively higher than that in B. prima 1.5 time exceeds height of the lateral lamina. (Karatajūte-Talimaa 1966); the ventral lamina is The dorso-lateral ridge (dlr) is well-defined. The 1.2-1.3 time as broad as the lateral lamina high. postnuchal ornamented corner (pnoa) is sharp, The ventro-lateral ridge (vlr) is well-defined. moderately long and narrow. Specimen LGI The pectoral fin is represented by many disartic- 5/2379 shows the dorsal overlap area partly ulated bones, and five specimens showing artic- overlapping the AMD plate. The processus ulated plates of the proximal segment. There are obstans is strongly developed (Karatajūte- 14 examples of the distal segment or it frag- Talimaa 1966). ments. The CV1 contacts the MM2. The CD1 is The MxL is moderately broad. The dorsal lami- of moderate size with L/B index varying from na of the plate is 1.4-1.6 time as long as it is 2.7 to 3.1 (2.8 on the average). The CV1 is slight- broad. The dorso-lateral ridge is well-defined. ly longer than the CD1 and have the L/B index The posterior oblique sensory line groove (dlg2) about 3.1-3.4 (3.2 on the average). The ML2 is terminates close to the lateral margin, in some 4.2-4.4 times as long as it is broad. The distal distance from the dorso-ventral pit-line groove segment shows only CD3. Both segments bear (dxp) crossing the dorso-lateral ridge. Specimen prominent lateral and mesial spines. On the LDM 307/6 has no posterior oblique sensory proximal segment the isolated mesial spines are line groove. The overlap area for the AMD is large and high. often restricted to half the length of the antero- The ornamentation is generally tubercular with dorsal margin (Karatajūte-Talimaa 1966) (LGI coarse tubercles and short vermiculated ridges 5/2485, 5/2490, 5/2491), as in Remigolepis of fused tubercles on the head-shield in well- (Stensiö 1931). grown individuals (Karatajūte-Talimaa 1966). The ventral lamina of the AVL is 1.6-1.8 time The short radially arranged ridges are developed as long as it is broad. The subcephalic division is along the margins of the La and Nu. The short and comprises about 20% of total length network of anastomosing ridges, which are bro- of the ventral lamina. The antero-lateral corner ken into short ridges could be sometimes seen is situated slightly medially the axis of the ven- on the posterior part of the Prm. The ornament tro-lateral ridge. The ventral lamina is 2.9- on the Sm consists of the network with weak 3 times as broad as the low lateral lamina high. elevations in the points of anastomoses on the The right AVL overlaps the left AVL. The central part of the plate and is almost smooth on axillary foramen (f.ax) is relatively large and the posterior part. The ornament is typically rounded or slightly elongated in shape tubercular in general on the dorsal and lateral (Karatajūte-Talimaa 1966). The visceral surface walls of the trunk-armour and reticular on the of the AVL shows the high transverse anterior ventral wall (Karatajūte-Talimaa 1966). The crista running almost mesially subparallel to the tubercles are usually relatively low, often fused gently defined low and broad transverse thick- forming the short, sometimes vermiculated ening (Karatajūte-Talimaa 1966), but neverthe- ridges. The tubercles and ridges are arranged

516 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

into rows, parallel to the mesial margin of the 4) relatively narrower anterior margin of the ADL and anterior margin of the MxL. The AMD; 5) relatively shorter pectoral fin. ornamentation is fine-tuberculated on the lateral B. obrutschewi can be distinguished from B. cel- wall of the trunk-armour. The ornamentation of lulosa (Gross 1941), other lower Frasnian the pectoral appendage also is variable. It is Bothriolepis representative from the Main reticulate in general, on the CD1 the ornament Devonian Field in 1) its smaller size; 2) tubercu- consists of radially arranged ridges of fused or lar ornamentation; 3) narrower head-shield; isolated tubercles. The network of ridges bears 4) shape of the Prm possessing more long weak elevations in the points of anastomoses on orbiral margin; 5) course of the infraorbital sen- the ML2 and CV1. The distal segment bears the sory line groove on the Prm and La; 6) shape of longitudinal well-defined ridges on the dorsal the Nu; 7) narrower lateral division of the Pn; wall. The ventral wall of the distal segment is 8) longer Sm; 9) features of the visceral surface almost smooth with gently defined ridges in its of the trunk armour; 10) CV1, which is making proximal part. contact with the MM2.

REMARKS The above account is the first full treatment in Bothriolepis cellulosa (Pander in Keyserling, 1846) English, which supplements Karatajūte- (Fig. 11) Talimaa’s description (in Russian) of Bothriolepis Pterichthys cellulosa Pander in Keyserling, 1846: obrutschewi (1966), using specimens from the 292. collection of the Latvian Museum of Natural Bothriolepis retinata Hoffman, 1911: 293, 297, figs 14, History and adding some details such as struc- 15; pl. 24, fig. 4. — Gross 1931: 58. — Stensiö 1931: ture of the visceral surface of the head shield. 11. Bothriolepis cellulosa (Pander) – Gross 1932: 24; 1933: DISCUSSION 36-39, figs 36-39; pl. 4, figs 1, 9, 10, 12, 15; pl. 5, fig. 12 Bothriolepis obrutschewi resembles B. prima, (in part). but may be distinguished by 1) its narrower head- TYPE SPECIMEN. — The head-shield f 147, Museum shield; 2) relatively broader dorsal and ventral für Naturkunde, Berlin, chosen by Gross among walls of the trunk-armour; 3) relatively longer specimen collected from the type locality (Gross 1933: taf. 4, fig. 15). subanal division of the PVL; 4) shape of the postlevator cristae on the visceral surface of the MATERIAL EXAMINED. — (Addition to the descriptions of Gross [1941] and Stensiö [1948]). LDM AMD; 5) proportions of the ADL; 6) more 43/673: fragment of the AMD; LUGM 6, 9, 10: strongly defined tubercular ornament; 7) devel- AMD; LUGM 2, 9, 12, 14: PMD; LUGM 5, 16: MxL; opment of the central sensory line groove (csl) and LUGM 2, 9, 13, 17: bones of the pectoral fin; LUGM the anterior oblique dorsal sensory line groove 2, 4, 8, 15: head-shields; NHM P.17807, 17810, 17813, 17814, 17818, 17826, 17828, 17829, 17836, 17837: Nu, (dlg1) in smallest individuals. B. obrutschewi AMD, 2 PMD, 4 MxL, AVL, four fin bones; RSM differs from B. evaldi in its 1) much broader 1964.26.41 (SMNH P.3275): impression of the AMD dorsal wall of the trunk-shield; 2) shape and and AVL. proportions of the AMD; 3) shape of the post- LOCALITIES AND HORIZON. — The type locality is nuchal ornamented corner of the ADL; 4) nar- an outcrop of dolomites, dolomite marls and clays ē rower ventral wall of the trunk-shield; 5) shorter at the right bank of P rse River (right tributary of Daugava River) near Koknese (Kokenhusen). The proximal segment of the pectoral fin. other studied material comes from Pastamuiža on B. obrutschewi resembles B. panderi by the Daugava River, Latvia; the lower Frasnian Pļaviņas ornamentation, but differs from it in 1) shape Regional Stage: Snetnaya Gora, Sēlija and Atzele ļ ņ and proportions of the head shield; 2) propor- Members of the P avi as Formation; and outcrop at the right bank of Velikaya River in Pskov near tions of the lateral division of the Pn, which is Piskovichi, Russia; Snetnaya Gora and Pskov Beds. narrower in B. obrutschewi; 3) broader AMD; The remains of this species were found in the

GEODIVERSITAS • 2001 • 23 (4) 517 Lukševičs E.

A C SM

p.br

AVL f.ax

AMD ADL

PVL vlr

MxL dlg2

PMD

dmr

FIG. 11. — A, head-shield of Bothriolepis cellulosa (Pander in Keyserling, 1846), lectotype (from Gross 1941: abb. 7 D); B, C, reconstruction of the trunk armour of Bothriolepis cellulosa in dorsal and ventral views (from Gross 1941: abb. 17, 18). Abbreviations: ADL, anterior dorso-lateral plate; AMD, anterior median dorsal plate; AVL, anterior ventro-lateral plate; MV, median ventral plate; MxL, mixilateral plate; PMD, posterior median dorsal plate; PVL, posterior ventro-lateral plate; SM, semilunar plate; dlg2, posterior oblique dorsal sensory line groove; dmr, dorsal median ridge of trunk armour; f.ax, axillary foramen; p.br, processus brachialis; vlr, ventro-lateral ridge of trunk armour. Scale bar: 10 mm.

Snetnaya Gora Member in several localities in west- Pizhma River of the Middle Timan, the Ust’ ern and eastern Latvia, e.g., outcrops along Daugava Srednyaya Beds and the Srednyaya Beds of the Ust’ River from Kaktiņi to the ruins of Koknese castle, Yarega Formation (Ivanov & Lukševičs 1996). ā ļ exposures at Amata River near K r i and along DIAGNOSIS. — Bothriolepis of moderate size with a ā ā Maz Jugla and Liel Jugla rivers, outcrops at Venta median dorsal armour length of at least 190 mm. ī ž ļķ River near Kuld ga and at Rie upe River near Ka i Head-shield is relatively broad, B/L index of 128-146, hamlet; Lithuania: borehole Berčiunai, 73-76 m 138 on the average, and comparatively flat in its pre- deep, borehole Pakapiai, 78.2-80.3 m deep. orbital division. Anterior margin of the head-shield is Additionally, B. cellulosa was correctly reported considerably shorter than posterior margin, slightly from more easterly boreholes at the middle reaches convex and rounded with a rostral angle. Preorbital of Onega River in Arkhangelsk region of Russia recess of simple type. Prm is broad, posterior margin (Ivanov 1990), in Izborsk (Slavyanskie Klyuchi), at is much shorter than the anterior margin. Pineal plate Ostenka River, in the Yam-Tesovo locality (pers. broader than long or about as broad as long. Nu is comm., A. Ivanov), borehole 7-Ost.-Staraya Russa, broad, L/B index of 65-81, 70 on the average. Lateral 154.4-152.0 m deep (Sorokin 1978: determination of division of Pn is comparatively broad. Dorsal wall of D. Obruchev), as well as from Ukhta River, South the trunk armour is not high and of moderate width. Timan, Lower Ust’ Yarega Formation, and from Tergal angle is situated in the foremost part of the

518 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

middle third of the AMD. Median dorsal ridge is marginal plate; 5) structure of the visceral sur- weakly developed and partly absent in large individu- face of the AMD; 6) character of the ornamenta- als. Postlevator crest usually present and often very strongly developed in its posterior part, forming there tion in large individuals. These two species seems to a certain extent a floor beneath the levator fossa. to be phylogenetically very closely related. Ventral tuberosity practically absent. AMD is moderately broad, B/L index 83-94, 89 on the average. PMD comparatively broad with B/L index 82-112, 96 on Bothriolepis panderi Lahusen, 1880 the average; anterior margin is broad, posterior corner (Figs 12; 21J) obtuse or rounded off. Pectoral fin fairly robust. Proximal segment is moderately long, 3.5 to 4 times as Bothriolepis panderi Lahusen, 1880: 137, taf. 1, figs 1- long as broad. The point contact between MM1 and 5; taf. 2, fig. 1 [non Figs 2-4]. — Gross 1932: 25 (in CV2 plates of pectoral fin results in separation of part). CV1 from MM2. Lateral spines of proximal segment LECTOTYPE. — The complete head shield and anterior comparatively short. Medial spines fairly strongly part of the trunk armour MM 1/96, chosen by Gross developed and independent; the median spines situat- (1932). ed on the CD1 and on the adjacent parts of the MM2 pointing dorsally. Ornamentation typically reticulate, MATERIAL EXAMINED. — SMNH P.3387, CD1; MM in small and medium-sized individuals of a fairly reg- 2/96, 3/96, fragments of the pectoral fin; LDM ular fine-meshed network of anastomosing ridges, 63/337, AVL, 63/338, ADL; GM 1/119, 2/119, 7/119, narrow and well-defined and with distinct tubercular fragments of AVL, 8/119 and 9/119, pieces of pectoral thickenings and elevations at their points of union. fin bones. These bones and lectotype is all so far avail- Ornament in quite lagre individuals retaining an on able material. the whole fine-meshed reticular character on the head-shield, but often dissolved into tubercles and LOCALITY AND HORIZON. — Right bank of Syas’ nodose tubercular ridges on the dorsal wall of the River not far from Montsevo village, Russia; the trunk armour. lower Frasnian Snetnaya Gora Beds. DIAGNOSIS. — Bothriolepis with a median dorsal trunk armour length of at least 125 mm. B/L index of REMARKS the head shield is 147. Rostral margin is convex, much Bothriolepis cellulosa is well-described by Gross shorter than the posterior margin. Orbital fenestra is (1941) and Stensiö (1948) and its diagnosis is to relatively small, short and broad, with a B/L index 180. Prm is relatively broad, B/L index is 100; the the large extent based on their descriptions, slightly convex orbital margin is much shorter than except for the measurements and estimated the rostral margin. Rostral plate is twice as broad as it indices. is long and bears deep and short nasal notch. Pineal plate is relatively broad with the concave anterior and lateral margins; the posterior margin is almost stright. DISCUSSION Outer surface of the plate is pierced by the pineal Bothriolepis cellulosa resembles B. panderi in opening. Nu relatively broad, L/B index of 61. Pmg is certain aspects, but differs from it in 1) the shape longer than broad with lateral margin much longer than the median margin. Trunk-armour is relatively and proportions of the Prm; 2) the shape of the broad, with somewhat elevated dorsal wall. AMD is Pi; 3) the shape and forward extension of the Pn moderately broad, B/L index about 71. The anterior in B. panderi; 4) the robust and relatively short- margin is moderately broad, 1.5 time shorter than the er proximal segment of the pectoral fin; 5) char- maximum breadth of the plate. The postlevator processes are strongly defined. Median dorsal ridge acter of ornamentation. (For the comparison of poorly developed. AVL is of moderate breadth with B. cellulosa with B. prima and B. obrutschewi, short subcephalic division; the anterior lateral corner see the descriptions of the latter presented of subcephalic division is situated in the middle above). between the median and lateral margins. Proximal segment of the pectoral appendage is relatively B. cellulosa is most closely resembling B. cana- long and slender, about five times as long as it is densis (Whiteaves, 1880) in several respects and broad; it bears prominent lateral and mesial spines, differs from this species just slightly in its the mesial ones are numerous, short and closely set- 1) narrower and more flattened head-shield; ting. CD1 of moderate size, L/B index about 2.6. The ornamentation consists of tubercles and short vermic- 2) narrower orbital fenestra; 3) broader lateral ulated ridges both on the head-shield and the trunk- division of the Pn; 4) shorter and higher sub- armour.

GEODIVERSITAS • 2001 • 23 (4) 519 Lukševičs E.

finished slightly anteriorly the level of middle of the orbital fenestra length. The Ro is much broader and shorter than in B. canadensis. The Pi is relatively broad, breadth slightly exceeds a length. The Pp is short and broad, L/B index is 156, with a slightly convex anterior margin. The Nu is deficient posteriorly, but seems to be relatively broad with a L/B index of about 61. The anterior division of the lateral margin is concave and a little shorter than the posterior division. There are short supraoccipital grooves, which terminate little in front of the obtected nuchal area at the rather large external openings for the endolymphatic ducts. The Pn is of moderate breadth, L/B index 82. The lateral division of the Pn is relatively nar- FIG. 12. — Bothriolepis panderi Lahusen, 1880, lectotype, the row and is composing 49% of the general complete head-shield and anterior part of the trunk armour MM 1/96. Right bank of Syas’ River near Montsevo village, Russia. breadth of a plate. Snetnaya Gora Beds. Scale bar: 10 mm. Three sclerotic plates in most features are similar to that of B. canadensis (Stensiö 1948: text- fig. 21). DESCRIPTION The dorsal wall of the trunk armour is higher Bothriolepis panderi attained a somewhat larger than that in B. cellulosa. The median dorsal ridge size than B. cellulosa. The length of the head is rather weakly developed, and both dorso- shield reaches about 60 mm, the dorsal length of lateral and ventro-lateral ridges are well-marked. the trunk armour is estimated at least about The anterior margin of the AMD is weakly con- 125 mm. The proportions and shape of the vex. The antero-lateral and lateral corners are head-shield resemble that of B. canadensis, but rounded. The posterior division of the lateral differs well from that in B. cellulosa. It is com- margin seems to be much shorter than the ante- paratively flat in its anterior part and slightly rior division. The tergal angle (dma) is situated vaulted in the posterior part. It seems to be rela- in between the anterior and middle thirds of the tively shorter than that in B. cellulosa. plate and is weakly marked. Overlap areas for In almost all aspects, the Prm looks similar to ADL and MxL are normally developed as usual- that in B. cellulosa and B. canadensis. It is broad- ly in Bothriolepis. est at the infraorbital sensory groove or rostral The dorsal lamina of the ADL is relatively nar- margin. The orbital margin seems to be devoid row and long, with massive postnuchal orna- the nasal notch. The rostral margin is not well- mented corner. A new specimen of AVL preserved in the lectotype and hence it is impos- collected from the type locality shows the ante- sible to decide whether or not the rostral angle is rior lateral corner of subcephalic division, which presented. is situated in the middle between the median and The La on the both sides of the lectotype are lateral margins and developed into a short broad crushed and therefore do not show several char- process (c.al, Fig. 21J). The visceral surface of acters. The rostral margin seems to be of moder- this specimen demonstrates the high transverse ate breadth. The infraorbital sensory groove anterior crista (cit1) running antero-mesially crosses the plate not far from its lateral and ros- and low and broad transverse thickening run- tral margins. The central sensory line groove is ning more mesially.

520 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

REMARKS and ADL, position of the tergal angle, the char- Lahusen (1880) erected a new species B. panderi acter of the ornamentation. (For the comparison for the remains of bothriolepids collected by of B. panderi with B. traudscholdi see the Pander & Trautschold from several localities at description of the latter). the Syas’ River. For the head-shield coming from Stolbovo locality and illustrated by Lahusen (1880: taf. 2, figs 2-4), Jaekel (1927) Bothriolepis traudscholdi Jaekel, 1927 (Figs 13-22) erected a new species B. traudscholdi. Gross (1932) proposed the head-shield MM 1/96 as a Bothriolepis panderi Lahusen, 1880: 137, taf. 2, lectotype of B. panderi and mentioned B. traud- figs 2-4. — Trautschold 1880: 172 (fig.). — Gross scholdi as synonimous to B. panderi without any 1932: 25 (p.p.); 1933: 39, 40, taf. 4, fig. 6; abb. 21; 1941: abb. 10B, C, 11G, H, 26H-K, 27D, E. — comments. Stensiö (1948) provided an extensive Stensiö 1948: 424; text-fig. 229A, 231 [non text- description of this species, based on the material fig. 230]. — Watson 1961: text-fig. 1. — Obruchev described by Lahusen (1880), Trautschold 1964: pl. 6, fig. 6. (1880) and Gross (1933). In 1988, the author Bothriolepis tremdscholdi – Jaekel 1927: 869, abb. 21. collected fragmentary AVL and ADL form the Bothriolepis traudscholdi Jaekel, 1927: 932, abb. 60. — type locality, and revisited all available material Gross 1932: 25; 1933: 40 (nomen negatum). from Syas’ River. In my opinion, specimens TYPE SPECIMEN. — Jaekel (1927) proposed a new from the Stolbovo site belongs to separate species of Bothriolepis for a head-shield collected species, namely B. traudscholdi (see below). by Trautschold (1880, shown also by Gross in Therefore the description of B. panderi provid- 1933) at Syas’ River not far from Stolbovo village (Russia), said to be held in the Museum of Breslau ed here differs greatly from those given by (now Wroclaw in Poland). Part of the Trautschold Gross (1933) and Stensiö (1948). collection is held in this museum, but the specimen shown by Jaekel cannot be located (pers. DISCUSSION comm. A. Ivanov). Therefore, I propose here the head-shield PIN 330/33, collected by J. Eglons in Bothriolepis panderi closely resembles B. cellu- 1937 at the type locality and illustrated by losa, but differs from it in features mentioned Obruchev (1964: pl. 6, fig. 6), as a neotype of above in the description of B. cellulosa. This Bothriolepis traudscholdi. species also seems to be closely related to MATERIAL EXAMINED. — PIN 330/39, 41-75, 77-98, B. canadensis, but differs in 1) position of the 100-107, 110-128, 29/1, 2, articulated head-shields infraorbital sensory groove; 2) much broader and disarticulated plates of the skull roof and trunk armour; PIN 2917/41-46, articulated head-shields and rostral plate; 3) higher dorsal wall of the trunk- anterior divisions of the trunk armour; LDM 63/1-33, armour; 4) more slender proximal segment of 35-51, 53-230, 241-396, IEC LP 12/1-5, disarticulated the pectoral fin. plates of the skull roof and trunk armour; IEC LP 12/6, The species B. panderi and B. taylori Miles, 1968 articulated plates of the dorsal trunk armour; NHM P.34465, sandstone block with 20 bones, including from Edenkillie Beds of Scotland (Miles 1968) articulated head-shields; RSM 1902.72.4, AMD, are clearly very close morphologically. They are 1902.72.6, PMD. Disarticulated plates of the head- similar in 1) the general proportions of the shield LDM 71/18, Prm, 71/51, Nu, 71/52, La; disar- trunk-armour; 2) the shape of the dorsal wall; ticulated plates of the trunk armour LDM 71/2, 34, 36, 38, 39, 42, 45, 47, 50, 87, 89-92, 97, 161 and plates 3) the absence of the dorsal median ridge; 4) the of the pectoral fin LDM 71/54-57, 62, 101, 125, 131, shape of the anterolateral corner of AVL; 5) the 132 are tentatively referred to this species. shape and proportions of the Prm. B. taylori dif- LOCALITIES AND HORIZON. — The type locality is an fers from B. panderi in its 1) larger size; 2) pro- outcrop of dark red-coloured sandstone with thin portions of the AMD; 3) shape of the CD1. layers of clayey siltstone, multicolored marl and clay, B. paradoxa (Agassiz, 1845) from the Scaat on the right bank of the Syas’ River near Stolbovo village, Russia. Other material comes from the outcrops Craig Beds differs from B. panderi in the shape at Syas’ River near Yukhora village, not far from of Prm, shape and proportions of Nu, AMD Stolbovo, and exposure of the dolomites at the left

GEODIVERSITAS • 2001 • 23 (4) 521 Lukševičs E.

C A F

B H

FIG. 13. — Bothriolepis traudscholdi Jaekel, 1927; A, B, head-shield PIN 330/113 in dorsal and visceral views; C, Prm PIN 330/126 in dorsal view; D, Prm PIN 330/127 in dorsal view; E, La PIN 330/124 in dorsal view; F, Pn LDM 63/138 in dorsal view; G, Nu LDM 63/149 in dorsal view; H, I, Nu and Pp PIN 330/42 in dorsal and visceral views; J, Nu LDM 63/156 in visceral view. Right bank of Syas’ River near Stolbovo village, Russia. Dubnik Formation. Abbreviations: La, lateral plate; Nu, nuchal plate; Pn, paranuchal plate; Pp, postpineal plate; Prm, premedian plate. Scale bar: 10 mm. bank of the Gauja River not far from Vidaga village, possible new form of Bothriolepis from the Latvia. All Russian material comes from the Frasnian Matusevich Formation of Severnaya Zemlya seems to Dubnik Formation. The Latvian material comes from be closely related to Bothriolepis traudscholdi from the Altovo Member of the Daugava Formation. A the Main Devonian Field (Lukševičs 1999).

522 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

G B

D E

FIG. 14. — Bothriolepis traudscholdi Jaekel, 1927; A, B, head-shield PIN 330/117 in dorsal and visceral views; C, head-shield PIN 330/125 in dorsal view; D, La PIN 330/115 in visceral view; E, La PIN 330/112 in dorsal view; F, Prm PIN 330/46 in dorsal view; G, H, Sm PIN 330/116 in lateral and visceral views; I, J, Sm PIN 330/114 in lateral and dorsal view. Right bank of Syas’ River near Stolbovo village, Russia. Dubnik Formation. Abbreviations: La, lateral plate; Prm, premedian plate; Sm, submarginal plate. Scale bar: 10 mm.

DIAGNOSIS. — Rather large Bothriolepis with a medi- strongly convex anterior margin shorter than posterior an dorsal armour length of at least 140 mm. Head- margin. Orbital fenestra long. Preorbital recess of sim- shield of moderate width, B/L index 133, with ple type. Nu moderately broad with B/L index of

GEODIVERSITAS • 2001 • 23 (4) 523 Lukševičs E.

soc B ifc1 AMD A fe.orb ADL ifc2 Prm lpr prh cir matrix

La csl fe.orb AVL F Pmg E Pp

Pn Nu

mp D C nm nprl Sm p pr.po CD1 g

ML2 ood

AMD ADL cr.tv G cr.pm cr.o ad2 H gr.sc I ad1

J ad1 B-J

FIG. 15. — Bothriolepis traudscholdi Jaekel, 1927; A, head-shield PIN 330/113 in dorsal view; B, head-shield, anterior part of AMD, left ADL, AVL, CD1 and CV1 PIN 2917/45 in lateral view; C, head-shield, anterior part of AMD, both ADL, right AVL and proximal segment of the pectoral fin PIN 2917/43 in dorsal view; D, head-shield PIN 330/117 in visceral view; E, Prm PIN 330/118; F, Nu LDM 63/149; G, La LDM 63/131; H-J, submarginal plates; H, PIN 330/116 in lateral view; I, J, PIN 330/114 in lateral and ventral views. Right bank of Syas’ River near Stolbovo village, Russia. Dubnik Formation. Abbreviations: ADL, anterior dorso-lateral plate; AMD, anterior median dorsal plate; AVL, anterior ventro-lateral plate; CD1, dorsal central plate 1; CV1, ventral central plate 1; La, lateral plate; ML2, lateral marginal plate 2; Nu, nuchal plate; Pmg, postmarginal plate; Pn, paranuchal plate; Pp, postpineal plate; Prm, premedian plate; Sm, submarginal plate; ad1, anterior articular process; ad2, posterior articular process; cir, semicircular pit-line groove; cr.o, median occipital crista of head-shield; cr.pm, paramarginal crista of head-shield; cr.tv, transverse nuchal crista of head-shield; csl, central sensory line groove; fe.orb, orbital fenestra; g, paired pits on Pp; gr.sc, groove, possible for sensory canal; ifc1, principal section of infraorbital sensory line; ifc2, branch of infraorbital sensory line diverging on La; lpr, lateral process of head-shield; mp, middle pit-line groove; nm, obtected nuchal area; nprl, prelateral notch; ood, otico-occipital depression; p, lateral pit; prh, preorbital recess; pr.po, antero-lateral corner of otico-occipital depression; soc, anterior section of the supraorbital sensory line. Scale bars: 10 mm.

524 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

ABC

D EF

FIG. 16. — Bothriolepis traudscholdi Jaekel, 1927, AMD; A, D-H, dorsal views; A, LDM 63/41; D, PIN 330/56; E, PIN 330/55; F, PIN 330/52; G, LDM 63/37; H, PIN 330/53; B, C, visceral views; B, LDM 63/44; C, PIN 330/57. Right bank of Syas’ River near Stolbovo village, Russia. Dubnik Formation. Abbreviation: AMD, anterior median dorsal plate. Scale bar: 10 mm. about 81; it is broadest across the postero-lateral cor- pectoral fin is slender, about 4.4 times as long as broad; ners. AMD moderately broad, B/L index about 94. it bears separate relatively small lateral and mesial The anterior margin 1.9 time shorter than the maxi- spines, which are almost similar to the tubercles, compo- mum width of the plate. Postnuchal notch pro- sing the ornamentation. The point contact between nounced, with very strong anterolateral corners. MM1 and CV2 of pectoral fin results in separation of Median dorsal ridge weakly developed and practically CV1 from MM2. The ornamentation is fine-meshed in absent in large individuals. PMD is relatively broad very small individuals, typically tubercular in medi- with B/L index about 104. Postnuchal ornamented um-sized individuals and has mixed character in large corner of the ADL is sharp, long and narrow. Axillary individuals, consisting of tubercles and anastomosing fenestra longer than high. Proximal segment of the ridges on the skull roof and plates of the trunk armour.

GEODIVERSITAS • 2001 • 23 (4) 525 Lukševičs E.

AB C H

dmr D f.retr E

alr

pt1

G mvr

grm npn F pr.pl dma

dlg2

oa.MxL

oa.PMD

FIG. 17. — Bothriolepis traudscholdi Jaekel, 1937, AMD; A-D, F-H, dorsal views; A, LDM 63/18; B, LDM 63/24; C, LDM 63/7; D, PIN 330/52; F, LDM 63/67; G, LDM 63/30; H, LDM 71/34; E, visceral view, LDM 63/13. Right bank of Syas’ River near Stolbovo village, Russia. Dubnik Formation. Left bank of Gauja River near Vidaga village, Latvia. Kranciems Member of the Daugava Formation. Abbreviations: AMD, anterior median dorsal plate; MxL, mixilateral plate; PMD, posterior median dorsal plate; alr, postlevator thickening; dlg2, posterior oblique dorsal sensory line groove; dma, tergal angle; dmr, dorsal median ridge; f.retr, levator fossa; grm, ventral median groove; mvr, median ventral ridge; npn, postnuchal notch; oa.MxL, area overlapped by MxL; oa.PMD, area overlapped by PMD; pr.pl, external postlevator process; pt1, anterior ventral pit. Scale bar: 10 mm.

DESCRIPTION from the Vidaga site are incomplete and usually This species is well-represented at the type deformed, in many cases preserved only as an locality by many disarticulated plates, as well as impressions. Most are from small or well-grown some articulated skulls and trunk shields, which individuals of moderate size, but there are also are usually well-preserved. Almost all specimens some quite large specimens.

526 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

A BD

C E

F K L

J H

G I

FIG. 18. — Bothriolepis traudscholdi Jaekel, 1927; A, PMD PIN 330/47 in dorsal view; B, PMD PIN 330/58 in visceral view; C, PMD PIN 330/48 in dorsal view; D, PMD LDM 63/58 in dorsal view; E, MxL PIN 330/94 in dorsal view; F, ADL LDM 63/98 in dorsal view; G, ADL PIN 330/86 in dorsal view; H, I, ADL PIN 330/87 in dorsal and lateral views; J, K, ADL PIN 330/98 in dorsal and anterior views; L, proximal segment of the pectoral fin PIN 330/68 in ventral view. Right bank of Syas’ River near Stolbovo village, Russia. Dubnik Formation. Abbreviations: ADL, anterior dorso-lateral plate; MxL, mixilateral plate; PMD, posterior median dorsal plate. Scale bar: 10 mm.

The length of the head shield reaches about 130-140 (of average 133, n = 4). It is strongly 75 mm, the dorsal length of the trunk armour is vaulted both rostrocaudally and transversely in estimated at least about 140 mm. The head shield small individuals, but is flat in the well-grown in- (Figs 13A, B; 14A-C; 15A-D) has B/L index is of dividuals. There are well-defined anterolateral

GEODIVERSITAS • 2001 • 23 (4) 527 Lukševičs E.

The visceral skull surface (Figs 13B; 14B; 15D) AB shows the broad otico-occipital depression (ood), which is well-defined by the paramarginal cristae (cr.pm). The antero-lateral corner of otico-occipital depression (pr.po) is narrow in its base, postero-lateral corner extends laterally dmr not over the middle of the Pn’s posterior margin. The transverse lateral groove is moder- C A, B, D ately broad and clearly defined. The small, deep lateral pit (p) is situated closer to a prelateral notch than to the orbital edge of La. The attachment areas for the Prl and Sm on the La differs slightly from that of B. canadensis (e.g., Stensiö 1948: fig. 12) in that the overlap area for Prl is only slightly visible from the ventral side, as in Bothriolepis sp. from Gogo or B. portalensis (see Young 1988: fig 66B, D). The median occipital crista (cr.o) is slightly defined, often it consists of several radially arranged small ridges. The oa.MxL transverse nuchal crista is prominent, with the median part extending anteriorly. The median ridge (mr) sharing the moderately deep paired pits (g) of Pp is low. D The Prm is relatively broad, B/L index 90-110, 99 on the average. Usually it is broadest somewhat posteriorly the infraorbital sensory groove. The rostral angle (ac) usually is absent. The shape of the rostral margin is variable, often it is convex. The orbital margin is gently convex and well shorter than the rostral margin. The pt2 nasal notch (pnn) on the orbital margin is not well-defined. The anterior section of the supra- pma cr.tp orbital sensory line (soc) usually is clearly defined. FIG. 19. — Bothriolepis traudscholdi Jaekel, 1927, PMD; A-C, dorsal views; A, LDM 63/76; B, LDM 63/71; C, LDM 63/58; The La is moderately broad with L/B index of D, visceral view, PIN 330/50. Right bank of Syas’ River near 130-143, 134 on the average. The rostral margin Stolbovo village, Russia. Dubnik Formation. Abbreviations: MxL, mixilateral plate; PMD, posterior median dorsal plate; is almost straight, the antero-median and cr.tp, crista transversalis interna posterior; dmr, dorsal median antero-lateral corners are well-defined. The ridge; oa.MxL, area overlapped by MxL; pma, posterior marginal area of PMD; pt2, posterior ventral pit. Scale bars: 10 mm. infraorbital sensory groove crosses the plate in its anterior part not far from the orbital and lateral margins. The central sensory line groove corners (alc) and a deep prelateral notch (nprl). (csl) usually is finished at the level of the anteri- The obtected nuchal area (nm) is of moderate or margin of the orbital fenestra. width, broadest on the Nu, and usually with The Pp is broad both in small and moderate- well-defined lateral and median processes. The sized individuals, L/B index varies from 57 to orbital fenestra is moderately large, long, with a 71. The anterior margin remains convex with B/L index about 150-167, 156 on the average. increasing size of individuals.

528 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

The Nu is moderately broad with a L/B index A 71-90, 81 on the average. The anterior division of the lateral margin usually is almost straight and well shorter than the posterior division. The shape of the posterior margin is variable, sometimes it is strongly concave, often bears the posterior process (mppr). The central sensory line C groove is clearly distinct. Usually there are short B oa.AMD pnoa supraoccipital grooves (socc), which terminate little in front of the obtected nuchal area at the f.art external openings for the endolymphatic ducts dlr (d.end). Postorbital crista (cr.pto) on the visceral lcg surface is moderately high. pro The Pn is moderately long, L/B index 71-103, 88 on the average. Sometimes (in PIN 330/115) it D bears short middle pit-line (mp). The lateral division of the Pn is moderately broad and is composing 45-68% of the general breadth of a plate. The Pmg is relatively broad with lateral margins longer than the median margins. E The submarginal (extralateral) plate (Figs 14E-J; 15H-J) is comparatively long with L/B index about 220-270. The dorsal margin has a prominent anterodorsal process (ad1) and a narrow posterior attachment area for the skull. The F posterior margin is almost straight, the ventral margin is weakly to strongly concave. A well- marked lateral notch is rather deep separating the plate into a short thick anterior division and more thin posterior division. The specimen PIN 330/116 (Figs 14G; 15H) shows a groove (gr.sc) running along the dorsal margin of the ornamented part of the plate in its posterior division, which is similar to that of Bothriolepis obrutschewi (pers. obs.) and B. macphersoni and has the character of a sensory groove. FIG. 20. — Bothriolepis traudscholdi Jaekel, 1927, ADL; A, PIN The trunk armour in individuals of moderate 330/86 in dorsal view; B, C, PIN 330/98 in dorsal and anterior views; D, E, PIN 330/87 in dorsal and lateral views; F, LDM size is known from a large amount of disarticu- 71/45 in dorsal view, somewhat flattened; A-E, right bank of lated plates and several anterior parts of articu- Syas’ River near Stolbovo village, Russia. Dubnik Formation; F, left bank of Gauja River near Vidaga village, Latvia. Kranciems lated armours, sometimes with articulated Member of the Daugava Formation. Abbreviation: ADL, anterior pectoral fins, of small individuals. dorso-lateral plate. Scale bar: 10 mm. The trunk-armour in individuals of small size as it is remained in specimens PIN 2917/41-46 is moderately broad, B/L index 86. It is relatively about 140 mm. The median dorsal ridge is well- low with moderately high dorsal wall. The max- defined in small individuals, weakly developed imum length of the dorsal wall, probably, is in medium-sized individuals and represented

GEODIVERSITAS • 2001 • 23 (4) 529 Lukševičs E.

d AB

oa.PMD dlg2

D C

cu dlr lcg E F c.al G cit1 cit2 p.br

f.ax

c.al

J I H

p.br cit1

FIG. 21. — Bothriolepis traudscholdi Jaekel, 1927; A-C, MxL; A, PIN 330/99; B, LDM 63/82; C, LDM 63/85; D-G, AVL; D, LDM 63/109 in ventral view; E, PIN 330/64 in ventral view; F, LDM 63/107 in ventral view; G, LDM 63/108 in visceral view; H, I, MV in ventral view; H, LDM 63/122; I, LDM 63/123. Right bank of Syas’ River near Stolbovo village, Russia. Dubnik Formation; J, Bothriolepis panderi Lahusen, 1880, anterior part of the AVL plate LDM 63/338 in visceral view. Right bank of Syas’ River near Montsevo village, Russia. Snetnaya Gora Beds. Abbreviations: AVL, anterior ventro-lateral plate; MV, median ventral plate; MxL, mixilateral plate; PMD, posterior median dorsal plate; c.al, antero-lateral corner of subcephalic division; cit1, crista transversalis interna anterior; cit2, transverse thickening on the visceral surface of AVL; cu, postero-ventral ornamented corner; d, dorsal corner; dlg2, posterior oblique dorsal sensory line groove; dlr, dorso-lateral ridge of trunk armour; f.ax, axillary foramen; lcg, main lateral line groove; oa.PMD, area overlapped by PMD; p.br, processus brachialis. Scale bar: 10 mm.

530 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

oa.AVL cm1 cm1 AB cf.MxL

cf.MV cm2 cm2

vlr

cf. PVL CV1 D

ML2 E MM2 ML2 CD1 CV2

MM2 ML2 CD2

FIG. 22. — Bothriolepis traudscholdi Jaekel, 1927; A, B, PVL; A, LDM 63/114 in ventral view; B, LDM 63/113 in visceral view; C, proximal segment of the pectoral fin PIN 330/68 in ventral view; D, part of the proximal segment of the pectoral fin LDM 63/132 in dorsal view; E, part of the proximal segment of the pectoral fin LDM 63/139 in dorsal view; F, CV1 LDM 63/158 in ventral view. Right bank of Syas’ River near Stolbovo village, Russia. Dubnik Formation. Abbreviations: AVL, anterior ventro-lateral plate; CD1, dorsal central plate 1; CD2, dorsal central plate 2; CV1, ventral central plate 1; CV2, ventral central plate 2; ML2, lateral marginal plate 2; MM2, mesial marginal plate 2; MV, median ventral plate; MxL, mixilateral plate; PVL, posterior ventro lateral plate; cf.MV, area overlapping MV; cf.MxL, area overlapping MxL; cf.PVL, area overlapping PVL; cm1, anteromesial corner of ventral lamina of PVL; cm2, middle corner of ventral lamina of PVL; dc, dorsal corner of lateral lamina of PVL; oa.AVL, area overlapped by AVL; vlr, ventro- lateral ridge. Scale bar: 10 mm.

only in its posterior part in large individuals. rior margin is generally convex, sometimes The dorso-lateral and ventro-lateral ridges are somewhat wavelike in shape, relatively long. well-marked in small individuals and are round- The anterior margin is usually 1.1 time longer ed in large individuals. than the posterior margin. The antero-lateral The AMD is moderately broad, B/L index vary- and lateral corners are well-defined. The poste- ing from 84 to 105, 94 on the average. The anterior division of the lateral margin is 1.5-1.9 time

GEODIVERSITAS • 2001 • 23 (4) 531 Lukševičs E.

shorter than the anterior division. The tergal along the whole plates in small individuals and angle (dma) is situated slightly posteriorly the in the posterior half of PMD in medium-sized anterior third of the plate. The median dorsal and large individuals. The anterior margin is 1.7 ridge (dmr) is well-developed on the small 17- to 2.2 times as long as the total width of the 23 mm long plates; it is slightly defined behind plate, it is variable in its shape, usually without the tergal angle on the plates of moderate size distinct anterior corner. The posterior margin with the length 24-25 mm. More large plates usually has rounded, sometimes concave or with the length over 26 mm have no median pointed posterior median corner. The lateral dorsal ridge. The postnuchal notch (npn) is margins of the plate generally overlapping the broad and shallow, the postlevator process MxL, but in LDM 63/58 there are narrow areas (pr.pl) is well-defined. The anterior oblique dor- along the lateral process of the PMD overlapped sal sensory line groove (dlg1) is gently defined by the MxL (Fig. 19C). only in smallest specimen LDM 63/17 which is On the visceral surface (Figs 18B; 19D), the ven- 17 mm long. The posterior oblique dorsal senso- tral median groove (grm) is clearly shown also ry line groove (dlg2) is clearly defined also on in small specimens, the ventral median ridge the plates of very large individuals. Specimen (mvr) is low with shallow posterior ventral pit, LDM 63/18 (Fig. 17A) shows the posterior which is situated in posterior half of the plate. oblique dorsal sensory line groove developed Posterior marginal area (pma) is relatively short. only on the left lamina of the plate. Overlap The ADL (Figs 18F-K; 20) has relatively elon- areas for ADL and MxL mostly are normally gated dorsal lamina. The posterior margin of the developed as usually in Bothriolepis, but in lateral lamina is approximately equal in breadth LDM 63/30 (Fig. 17G), 63/8, and 71/34 to the posterior margin of the dorsal lamina. The (Fig. 17H) sutural connection of AMD with lateral lamina is about three times as long as it is MxL is of Remigolepis type. The antero-lateral deep. The dorso-lateral ridge is well-marked in margins in LDM 63/37 (Fig. 16G) and PIN the posterior part of the plate. The postnuchal 330/53 (Fig. 16H) are partly overlapped by ornamented corner (pnoa) resembles that of ADL, in 63/14 such overlapped area is devel- B. ciecere; in large specimens it is more broad. oped on the right side (the left side is broken). Notch behind it is poorly formed. The dorsal The visceral surface of the AMD (Figs 16B, C; margin of the plate bears an overlap area for the 17E) shows a moderately broad levator fossa AMD usually along the whole of its length, but (f.retr), which is limited by the low postlevator in specimens PIN 330/86 (Figs 18G; 20A) and thickenings (alr). The supranuchal area (sna) is 330/98 (Figs 18J; 20B) the ADL overlaps the clearly seen, but relatively narrow. The median AMD by its posterior half. Processus obstans is ventral ridge (mvr) and the median ventral well-developed, with high articulation lamina. groove (grm) are developed similar as in other The articular fossa for the exoskeletal cervical Bothriolepis. joint (f.art) is clearly demarcated by well-devel- The PMD is variable, usually broad, sometimes oped supra- and infra-articular cristae (crs, cri) very broad (in LDM 63/65), or relatively nar- (Figs 18K; 20C). row (in PIN 330/47 and PIN 330/48), B/L index The MxL (Figs 18E; 21A-C) has a comparative- varies from 91 to 112, 104 on the average. ly low lateral lamina which is more than 3 times Whether the differences in proportions of the as long as it is deep, and a relatively broad dorsal plate reflects sexual dimorphism or even pres- lamina about 1.6-1.7 time as long as it is broad. ence of two species within the material, is very The anterior margin concave or wavy. Dorsal hard to say, because in other respects narrow and lateral laminae meet at an angle of about and broad plates does not differ. The PMD is 113°. Dorsolateral ridge is well-marked, in large anteriorly almost flat and arched in the posterior specimens it is rounded. Overlap area for the part. The dorsal median ridge is well-marked AMD in specimen PIN 330/94 (Fig. 18E) is

532 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

restricted to half the length of the antero-dorsal Pm, partly La, Pn and Pp. The ornament on the margin, as in Remigolepis. Sm consists of ridges and tubercles. The orna- The AVL (Fig. 21D-G) is comparatively broad, ment on the plates of the trunk armour is typical- the ventral lamina is 1.5-1.8 time as long as it is ly tubercular in general, but retains its very broad. The subcephalic division comprises 20- variable character. Some plates have all possible 25% of the total length of a ventral lamina. The patterns of the ornament on their surface, espe- ventral lamina 2.1-3 times as broad as the lateral cially in large specimens. The ornamentation of lamina high. The lateral lamina is low, 3- the pectoral appendage is also variable. It is retic- 3.8 times as long as it is high. The ventro-lateral ulate in general, on the CD1 and dorsal lamina of ridge is well-defined, sometimes rounded off. the ML2 the network ridges bear tubercles in the The axillary foramen (f.ax) is rather large and points of anastomoses only along the lateral mar- elongated. The visceral surface of the AVL gin, more well-developed in proximal part. The shows the high transverse anterior crista (cit1) ornament on the ventral side of the pectoral running antero-mesially very close to the broad appendage is reticular in general. transverse thickening (cit2). The PVL (Fig. 22A, B) is of moderate breadth, REMARKS the ventral lamina is 2-2.5 times as long as it is Bothriolepis traudscholdi was illustrated by broad. The subanal division is relatively broad Jaekel (1927) as a new species from Syas’ River and long, it occupies about 30-36% of the total which differs from B. panderi, but he did not PVL length. The lateral lamina is moderately provide its description. This species was named high, 1.8-2 times long as it is high. The ventral as “Bothriolepis tremdscholdi n. sp.” in explana- lamina 1.2-1.3 time as broad as the lateral lamina tion to abb. 21 and “B. traudscholdi Jkl.” in high. The ventro-lateral ridge (vlr) is well- abb. 60 of Jaekel’s (1927) paper; both were defined. regarded to be misprintings by Gross (1933) and The pectoral fin is represented by many disartic- he incorrectly changed the original spelling into ulated bones, and four specimens showing artic- B. trautscholdi in a list of synonyms to B. pan- ulated plates of the proximal segment (Figs 18L; deri. However, in the catalogue of antiarchs, 22C-F). The comparatively slender proximal Gross (1932) have used the name B. traudscholdi, segment bears separate relatively small lateral but did not clearly define this action. Therefore, and dorsally directed mesial spines; the latter are acting as a first reviser, I propose here to choose usually similar to the tubercles composing the the name Bothriolepis traudscholdi as a valid ornamentation. The proximal segment is 4.1- name for this taxon. Gross (1933) mentioned 4.6 times as long as it is broad. The CD1 is of B. traudscholdi as a synonymous to B. panderi, moderate size with L/B index varying from 2.6 but without any further comments. Stensiö to 3.1 (2.8 on the average, n = 4). The CV1 is rel- (1948) agreed with Gross (1933) and provided atively more elongated and have the L/B index description of B. panderi including material, about 2.8-3.6 (3.2 on the average). The ML2 is which I suppose to be attributable to B. traud- 4.8-5.7 (5.2 on the average) times as long as it is scholdi. The description of B. traudscholdi here broad. is based on extensive material from the type The ornamentation is fine-meshed reticulate in locality, gathered by J. Eglons & D. Obruchev very small individuals, e.g. 18.9 mm long PMD in 1937, L. Lyarskaja in 1974, and author plate LDM 63/270, and typically tubercular in together with A. Ivanov in 1988. This material general in medium-sized and quite large individ- was never described in details, being only men- uals, becoming coarser and sparser. It consists of tioned as belonging to B. panderi (e.g., coarse tubercles and anastomosing ridges of Obruchev 1964). Specimens from Vidaga site at fused tubercles on the head shield. The tubercles Gauja River were collected by Lyarskaja in 1978 cover usually almost all the surface of the Prm, and the author together with Lyarskaja in 1983.

GEODIVERSITAS • 2001 • 23 (4) 533 Lukševičs E.

A A

C B B

FIG. 24. — Bothriolepis maxima Gross, 1933; A, head-shield FIG. 23. — Bothriolepis maxima Gross, 1933; A, head-shield LDM 99/1 in visceral view; B, Nu LDM 99/5; C, Prm LDM 99/2. LDM 99/1 in dorsal view; B, Nu LDM 99/6. Right bank of Imula Right bank of Imula River near Kalnarāji hamlet, Latvia. Ogre River near Kalnarāji hamlet, Latvia. Ogre Formation. Formation. Abbreviation: Nu, nuchal plate; Prm, premedian Abbreviation: Nu, nuchal plate. Scale bars: 20 mm. plate. Scale bars: 20 mm.

DISCUSSION of the Prm and Nu, relative length of the anteri- Bothriolepis traudscholdi resembles B. panderi or margin of the AMD, shape and proportions by several features: 1) the general shape of the of the PMD, ADL and MxL, as well as more head-shield; 2) proportions of the Pn and Pmg; elongated pectoral fin. B. traudscholdi can be 3) general proportions of the trunk armour; distinguished readily from B. cellulosa by larger 4) weak development of the dorsal median size, shape and proportions of the La and Nu, ridge; 5) position of the tergal angle; 6) propor- relative length of the anterior margin of the tions of the ADL; 7) proportions of the slender AMD, shape and proportions of the AMD, pectoral fin. Nevertheless, B. traudscholdi differs PMD and MxL, more elongated pectoral fin and considerably from B. panderi in its 1) compara- tubercular rather than reticular ornamentation. tively narrower head-shield; 2) more vaulted anterior part of the head-shield; 3) larger and Bothriolepis maxima Gross, 1933 longer orbital fenestra; 4) shape and proportions (Figs 23-28) of the Prm and Nu; 5) more anterior extent of the central sensory line groove; 6) more broad AMD; Bothriolepis maxima – Gross 1932: 25 (nomen 7) shorter anterior margin of the AMD; 8) shape nudum). of the postnuchal ornamented corner of the ADL; Bothriolepis maxima Gross, 1933: 41-43; taf. 5, fig. 14. 9) longer subcephalic division of the AVL. HOLOTYPE. — The head-shield f124 Geologisch- B. traudscholdi differs well from B. obrutschewi Paläontologische Institut und Museum der in its strongly larger size, shape and proportions Universität Berlin.

534 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

MATERIAL EXAMINED. — LDM 43/675, 99/1, 84/67, soc three articulated head-shields; PIN 1652/2, articulat- A ed head-shield and dorsal trunk armour; LDM 15/20, 23, 25-31, 125; 43/676-710, 43/712-721; 84/1-14, 17- 19, 21-30, 33-38, 40-47, 66; 87/1, 3, 4, 7-9, 11, 13, 14, 18; 99/2-44; PIN 89/3; 1491/87, 96-98; 1737/62-64; 1767/61; 2917/21,24-33, 35, 37-39, 41-44, 51-53, dis- ifc1 articulated plates of the head-shield, trunk armour and pectoral fin; LUGM 872, 1105: 2 MV.

LOCALITIES AND HORIZON. — The type locality of Bothriolepis maxima is the outcrop of the Ogre Formation sandstones at Imula River not far from Lankserde hamlet, Latvia; Ogre Formation. Other material came from the other outcrops at Imula River pnn near Kalnarāji hamlet and Vītiņi hamlet, exposure and caves Velna Ala at Abava River, outcrops along Ogre River, outcrop at Mūsa River close to Ceraukste vil- B lage, the Ogre Formation; exposure at the right bank mc of Daugava River near Lielvārde castle, exposure at csl Pp the right bank of Liepna River not far from Katleši village, Kuprava quarry for mining clays, Latvia; š Katle i Formation. In Russia, B. maxima have been Nu found by D. Obruchev in the outcrop of sandstone, clay and sand of the Prilovat’ Formation at Lovat’ River close to Kurskoye Gorodische village and at the pc middle current of Lovat’ River near Luka village. B. maxima was reported from the outcrops along Verkhnyaya Paluitsa and Nizhnyaya Paluitsa River surrounding Shugozero village, Tikhvin district of nm mppr d.end Leningrad region (Ivanov & Khozatski 1986). In

Lithuania, B. maxima is found in outcrops along FIG. 25. — Bothriolepis maxima Gross, 1933; A, Prm PIN Nyamunelis River near Didžpanemunis and 2917/53 in dorsal view; B, Nu and Pp PIN 2917/52. Lovat’ River Pakalniečiai, and from borehole Stačiunai, 139.4- near Luka village, Russia. Prilovat’ Formation. Abbreviations: 139.7 m deep, and borehole Petrašičnai, 57.8-58.0 m Nu, nuchal plate; Pp, postpineal plate; Prm, premedian plate; deep; Pamūšis Formation (Kratajūte-Talimaa pers. csl, central sensory line groove; d.end, opening of canal for endolymphatic duct; ifc1, principal section of infraorbital senso- comm.). B. maxima is recorded also from the ry line on head-shield; mc, lateral corner; mppr, posterior Jēkabpils quarry, the Katleši Formation (Sorokin process; nm, obtected nuchal area; pc, postero-lateral corner; 1978). B. maxima zone corresponds to the middle pnn, nasal notch; soc, anterior section of the supraorbital sen- Frasnian gigas conodont zone. Bothriolepis cf. maxi- sory line. Scale bar: 10 mm. ma is characteristic for the upper part of the Matusevich Formation of Severnaya Zemlya (Lukševičs 1999a). rounded. AMD about as long as it is broad, B/L index DIAGNOSIS. — A Bothriolepis with the median dorsal 86-107, 97 on the average, with narrow anterior mar- length of the armour reaching more than 500 mm. gin. PMD usually broader as it is long, B/L index Head-shield short and broad, B/L index about 137- about 96-117, 107 on the average; anterior margin of 156, 145 on the average, with almost flat preorbital moderate breadth, posterior corner rounded off. division. Anterior margin just slightly shorter than Dorsal lamina of ADL about twice as long as broad, the posterior margin, gently convex, sometimes with relatively narrow posteriorly the well-defined pro- a rounded rostral angle. Processus obstans relatively nounced postnuchal corner; lateral lamina low. short. Preorbital recess of trifid type. La relatively Dorsal lamina of MxL comparatively broad, from short. Nu broad and short, L/B index of about 68-75. about 1.5 to 1.6 time as long as broad; lateral lamina Lateral division of the Pn relatively narrow. Trunk low, about 3.5 times as long as high. Both laminae armour relatively low with a moderately flat dorsal enclosing an angle about 90°. Ventral lamina of wall. Dorso-lateral ridges are gently defined and AVL about one and a half times as long as broad. MV rounded in their anterior part, dorsal median ridge is relatively large. Pectoral fin fairly robust, moder- weakly developed and practically absent in large indi- ately long and narrow. Proximal segment about viduals. Tergal angle situated in the foremost part of 4.5 times as long as broad; distal segment narrow, the middle third of the AMD. Ventro-lateral ridges rounded in transverse section. CD5, CV5 and MM5

GEODIVERSITAS • 2001 • 23 (4) 535 Lukševičs E.

ABnpn

pr.pl

dma

dlg2

oa.MxL

oa.PMD

FIG. 26. — Bothriolepis maxima Gross, 1933, AMD; A, PIN 2917/42, slightly deformed; B, PIN 1737/63; C, PIN 1737/64; D, PIN 2917/43; A, D, Lovat’ River near Luka village, Russia. Prilovat’ Formation; B, C, Velna ala (Devil Cave) at the left bank of Abava River, Latvia. Ogre Formation. Abbreviations: AMD, anterior median dorsal plate; MxL, mixilateral plate; PMD, posterior median dorsal plate; dlg2, posterior oblique dorsal sensory line groove; dma, tergal angle; npn, postnuchal notch; oa.MxL, area overlapped by MxL; oa.PMD, area overlapped by PMD; pr.pl, external postlevator process of AMD. Scale bar: 20 mm.

are present. Lateral and median spines of proximal DESCRIPTION segment short and gently defined. Ornamentation This is the largest known Bothriolepis species reticulate, in quite large individuals retaining an on (Gross in Stensiö 1948). The largest complete the whole reticular character, with concentrically AMD LDM 99/11 is 216 mm long, exceeding the arranged ridges; tubercular and radially arranged on largest British species, B. gigantea. The largest the head-shield anteriorly the infraorbital sensory groove, anterior and posterior parts of the ventral specimens with thick plates comes from Latvia, wall of the trunk armour. The ornament become Imula and Abava River localities; the remains of smooth on the pectoral fin; well-defined only in the the same species from the east part of the distri- anterior part of the CD1, CV1 and ML2. bution area are usually smaller and less massive.

536 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

The head-shield (Fig. 23A) has the anterior margin which is only slightly shorter than the posterior margin, unlike all the other Frasnian bothriolepidoids from Baltic area. The anterior portion of the head-shield (anteriorly the orbital AMD fenestra) is slightly elongated in comparison ADL with that in such species as B. obrutschewi or B. cellulosa. Obstantic process is short, ending anteriorly quite well behind the transverse plane of the posterior margin of the orbital fenestra. This feature allows to distinguish B. maxima MxL from B. gigantea which possess a long obstantic margin (Miles 1968). The visceral surface of the head-shield (Fig. 24A) shows close resemblances with that PMD in B. gigantea. The antero-lateral corner of otico-occipital depression extends forward far over the transverse plane of the anterior margin of the orbital fenestra. The paranuchal crista is straight on the La making the floor under the FIG. 27. — Bothriolepis maxima Gross, 1933, reconstruction of lateralmost part of the anterior postorbital the trunk armour based on specimen PIN 1652/2. Right bank of process of endocranium, and of an irregular Lovat’ River near Luka village, Russia. Prilovat’ Formation. Abbreviations: ADL, anterior dorso-lateral plate; AMD, anterior shape on the Pn. The transverse lateral groove is median dorsal plate; MxL, mixilateral plate; PMD, posterior broad and shallow. The lateral pit is small, median dorsal plate. Scale bar: 20 mm. shallow and weakly defined, situated just in front of a prominent anterior crista of the transverse lateral groove, almost equally spaced The complete trunk armour PIN 1652/2 from an orbital edge of the La and prelateral (Fig. 27) is low and broad with a flat and low notch. The lateral margin shows very broad dorsal wall (Obrucheva 1974). Unfortunately it attachment areas for the Sm (Gross in Stensiö is almost impossible to measure correctly the 1948). The orbital edges of the Prm and La are angles enclosed by the dorsal and lateral wall, as just slightly thickened, but not so thick as that in well as the lateral and ventral wall due to the B. ornata. deformation of the trunk-armour plates during The Prm (Figs 24C; 25A) is relatively broad, fossilization. B/L index of about 99-113, 104 on the average. The AMD (Fig. 26) is about as long as it is broad The La is relatively broad with the L/B index with B/L index 86-107, 97 on the average. Its 125-134, 131 on the average. The Nu (Figs 23B; anterior margin is narrow, more than twice 24B; 29B) is relatively broad with the L/B index (from 2.2 to 3.3 times) as long as the plate is of about 68-75, 71 on the average. It is usually broad (Gross in Stensiö 1948) resembling broadest across the posterior lateral corners or Bothriolepis ornata in that respect. The propor- sometimes across the lateral corners, just like as tions of the lateral margin of AMD vary signifi- in B. gigantea (Miles 1968). The Pn has a L/B cantly among specimens coming from different index of about 73-83, 79 on the average, with the localities: the posterior division of the lateral mesial division slightly broader than long. The margin is 1.3-1.9 time shorter than the anterior lateral division of the Pn is relatively narrow division in specimens from Latvia, and the same (Gross in Stensiö 1948), composing only 44- index in specimens from Luka locality in Russia 48% of the total breadth of the plate. reaches 1.7-2.6. Overlap areas for ADL and

GEODIVERSITAS • 2001 • 23 (4) 537 Lukševičs E.

A MxL are normally developed as usually in pro pnoa Bothriolepis in general (Gross in Stensiö 1948), but in one case (LDM 99/11) the sutural connection of AMD with MxL is of Remigolepis type on the right side of the plate: the AMD overlaps the anterior part of the right MxL. The anterior margin of PMD is of moderate breadth, 1.7-2.1 times as long as the plate totally oa.AMD lcg broad. The ADL is not simply overlapped by the AVL, but also at the same time overlaps that plate posteriorly the processus obstans, as in dlr Bothriolepis ornata and B. groenlandica. The PVL (Fig. 28B) is relatively broad, the ventral lamina is from 1.8 to 2.2 times as long as it is broad. The subanal division occupies about 30% of the total PVL length.

REMARKS Latvian material encounted here have been col- B oa.AVL cm1 lected by Gross, Lyarskaja and the author from type locality and other site close to the type area. Russian material from Lovat’ River is col- cm2 lected and illustrated by Obruchev (1947) and Obrucheva (1974), but has never been described in details.

DISCUSSION As the largest species of the genus, Bothriolepis oa.PVL maxima differs well from all the other repre- vlr sentatives of the group from Baltic area first of all in its great size and very thick bones. Smallest specimens of B. maxima are much bigger than B. evaldi (for the comparison of both species see the description of B. evaldi), and they differ considerably from the other Baltic species in the proportions of the AMD, PMD, MxL and AVL. All the early and middle Frasnian Bothriolepis in this area could

FIG. 28. — Bothriolepis maxima Gross, 1933; A, ADL PIN be well-recognized by their preorbital recess 1491/98, Velna ala (Devil Cave) at the left bank of Abava River, of a simple type, and only B. maxima among Latvia. Ogre Formation; B, PVL PIN 1491/88, right bank of Bolshoy Tuder River near Medovo village in vicinity of Cholm them possess the preorbital recess of a trifid town, Russia. Prilovat’ Formation. Abbreviations: ADL, anterior type. B. maxima resembles Bothriolepis gigan- dorso-lateral plate; AMD, anterior median dorsal plate; AVL, anterior ventro-lateral plate; PVL, posterior ventro lateral plate; tea (Stensiö 1948; Miles 1968) from Scotland in cm1, anteromesial corner of ventral lamina of PVL; cm2, middle several aspects and these species seems to be corner of ventral lamina of PVL; dlr, dorso-lateral ridge of trunk armour; lcg, main lateral line groove; oa.AMD, area overlapped very closely related phylogenetically. Never- by AMD; oa.AVL, area overlapped by AVL; oa.PVL, area over- theless, as it was pointed out by Gross (in lapped by PVL; pnoa, postnuchal ornamented corner; pro, processus obstans; vlr, ventro-lateral ridge. Scale bars: 20 mm. Stensiö 1948), Stensiö (1948) and Miles (1968),

538 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

there are several features distinguishing these Postlevator cristae on the visceral surface of AMD are two species. Adding the list of such a features well-defined. AMD overlaps the MxL by the anterior part of the posterior division of lateral margin in provided by Miles, it is possible to suggest that medium-sized individuals. PMD moderately broad B. maxima differs from B. gigantea in its with pronounced posterior corner. Dorsal lamina of 1) shorter obstantic margin; 2) presence of the MxL about 1.6-2.2 times as broad as the lateral lamina lateral pit on the visceral surface of the La; is high. The dorso-ventral pit-line groove on the MxL is usually present. Proximal segment of the pectoral 3) well-defined nasal notches on the Prm; appendage moderately long, about 3.6 times as longs 4) other shape of the posterior margin of the as it is broad and less then twice longer than the distal head-shield; 5) structure of the transverse segment. Ornamentation fine reticulate, becoming nuchal crista; 6) more sharp angle between the slightly coarser and sparser in medium-sized individuals. dorsal and lateral laminae of the MxL. DESCRIPTION This species is well-represented at the type Bothriolepis evaldi Lyarskaja, 1986 locality by many articulated head-shields, (Figs 29-31) trunk-armours and pectoral appendages, as well as some disarticulated plates. Most specimens Bothriolepis evaldi Lyarskaja, 1986: 123-130; pl. I, from this locality are slightly flattened, often fig. 1. deformed. Size range is from a median dorsal HOLOTYPE. — Articulated head-shield, trunk-armour trunk-armour (LDM 67/10, Fig. 29G) less than and pectoral appendages LDM 67/86. 17 mm long to an individual with a median dor- MATERIAL EXAMINED. — LDM 67/2-4, 67/6-77, sal armour length estimated of about 34 mm. 67/79, 67/80, 67/89-93: 62 articulated head-shields, trunk-armour and pectoral appendages, as well as 18 Material from the Kaibala site is represented by disarticulated plates of the armour from the type larger plates, an articulated head-shield LDM locality; LDM 280/1: head-shield, 280/2-27: mostly 280/1 (Fig. 30D) suggests a median dorsal disarticulated plates of the trunk armour and pectoral armour length estimated of about 48 mm. The fin from the Kaibala River site. head-shield is well-preserved in 22 specimens. It LOCALITIES AND HORIZON. — The type locality is relatively broad in small individuals, Kalnamuiža-1 (number 5 in Fig. 1) is cliff at the left bank of Amula River downstream from water-mill Lyarskaja (1986) mentions B/L index varying Kalnamuiža with grey sandstone and thin layers of from 118 to 170, but my measurements and esti- blue marls; the Middle Frasnian, the Rembate mations show the B/L is 140-157, 145 on the Member of the Ogre Formation (Lyarskaja 1986). average (n = 8), and reaching only 120 in medi- Other material comes from an outcrop exposing similar deposits at the right bank of Kaibala River (num- um-sized individual. The head-shield is strongly ber 12 in Fig. 1) 200 m from the estuary, not far from vaulted both rostrocaudally and transversely ruins of Lielvārde castle. (Lyarskaja 1986). The rostral margin is convex, DIAGNOSIS. — Small Bothriolepis with a median dor- shorter than the posterior margin; the antero- sal armour length reaching about 50 mm. B/L index lateral corners and a shallow prelateral notch are of trunk armour about 95. B/L index of the head- clearly defined only in individuals of medium shield 140-157. Rostral margin of the head-shield strongly convex. Orbital fenestra relatively small, size (Lyarskaja 1986). The obtected nuchal area broad, slightly less than twice as broad as it is long. is short, broadest on the Nu. The orbital fenestra Nu arched, moderately broad, L/B index of 69. is relatively small, but very broad with a B/L index Trunk-armour of moderate height with broad and about 168-196, 185 on the average. A new mate- high dorsal wall. Dorsal and lateral walls of trunk enclosing an angle about 126° on MxL. Dorso-lateral rial (LDM 280/1) allows to identify the shape of and ventro-lateral ridges well-marked. Median dorsal the preorbital recess, which is of simple type. ridge well-defined posteriorly the tergal angle. The visceral skull surface shows the normal fea- Ventral wall of the trunk-armour relatively narrow, tures as a prominent transverse nuchal crista, B/L index 43-48. AMD broad, B/L index 84-108, arched, with right and left laminae forming an angle well-developed median occipital crista, and a of about 128°. Anterior margin broad, almost straight. very broad otico-occipital depression which is

GEODIVERSITAS • 2001 • 23 (4) 539 Lukševičs E.

D A C

B-F

E F

A, E B

FIG. 29. — Bothriolepis evaldi Lyarskaja, 1986; A, holotype, articulated head, trunk and pectoral fin armour LDM 67/86 in dorsal view; B, AMD LDM 67/7; C, articulated head and trunk armour LDM 67/14 in dorsal view; D, articulated trunk armour LDM 67/2 in dorsal view; E, articulated head, trunk and pectoral fin armour LDM 67/39; F, head and trunk armour in visceral view with articulated right pectoral fin in ventral view LDM 67/6; G, articulated trunk armour LDM 67/10 in dorsal view. Kalnamuiža 1 locality at Amula River, Latvia. Ogre Formation. Abbreviation: AMD, anterior median dorsal plate. Scale bars: 5 mm. well-defined by the paramarginal cristae. The margin can be recognized only slightly in medi- median ridge sharing the broad paired pits of Pp um-sized specimen LDM 280/1. There is a is low. median elevation inside the rostral margin. The The Prm was not described by Lyarskaja (1986). infraorbital sensory groove crosses the plate in It is broad, much broader than it is long in small its anterior part. specimens with B/L index 150-182, which The La is moderately broad with the L/B index decreases to 103 in largest individuals. The Prm 126-143, 134 on the average. The infraorbital is broadest at the infraorbital sensory groove or sensory groove crosses the plate in its anterior rostral margin. The rostral margin is convex, it is part not far from the orbital and lateral margins 1.2-1.4 time longer then the almost straight (Lyarskaja 1986). The central sensory line orbital margin. The nasal notch on the orbital groove (csl) usually is finished at the level of the

540 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

A-C

D-F

FIG. 30. — Bothriolepis evaldi Lyarskaja, 1986; A, details of the head-shield of specimen LDM 67/14 in dorsal view; B, details of the head-shield of the holotype, LDM 67/86; C, details of the head-shield of specimen LDM 67/39 in dorsal view; D, head-shield LDM 280/1 in dorsal view; E, somewhat flattened and deformed articulated head, trunk and left pectoral fin armour LDM 67/13 in ventral view; F, articulated head, trunk, left pectoral fin armour and right CV1 LDM 67/3 in ventral view; A-C, E, F, Kalnamuiža 1 locality at Amula River, Latvia; D, Kaibala River not far from Lielvārde, Latvia. Ogre Formation. Abbreviation: CV1, ventral central plate 1. Scale bars: 5 mm. middle of the orbital fenestra length, sometimes bital sensory line diverging on La (ifc2) are well- it extends almost to the anterior margin of the defined (Lyarskaja 1986). orbital fenestra (Lyarskaja 1986). The semicircu- The pineal plate is moderately narrow, slightly lar pit-line groove (cir) and branch of infraor- longer than it is broad, and not quadrate, as has

GEODIVERSITAS • 2001 • 23 (4) 541 Lukševičs E.

Ro A Pi been shown by Lyarskaja (1986). The all four Prm SCLR1 margins of the plate are concave. Position of the SCLR2 csl pineal pit is marked on the outer surface by the La Sm pineal elevation (Lyarskaja 1986). Pp AVL Nu Pmg The Pp is broad in small individuals and of Pn socc moderate breadth in maturity, L/B index varies dlg1 AMD from 44 to 55. Lyarskaja (1986) claimed that the CD1 shape of the plate is almost constant, but in fact ADL dlg2 the anterior margin is strongly convex in small ML2 specimens and became more straight with MxL increasing size, as in other species of Bothriolepis. The Nu has L/B index 64-76, 69 on the average. The plate is broadest across the lateral corners CD2 (Lyarskaja 1986). The anterior division of the PMD ML3 lateral margin usually is concave and a little CD3 shorter than the posterior division. The posteri- ML4 or margin usually is almost straight, the posteri- La or process is weakly defined. The central B Prm sensory line groove is clearly distinct (Lyarskaja 1986). In some cases there are long supraoccipital grooves (socc), which cross the plate little in AVL front of the obtected nuchal area and extend to the Pn. The external openings for the endolym- CV1 phatic ducts (d.end) are rather large, closely set one to another. Postorbital crista on the visceral MM1 surface is low, clearly seen only in largest indi- ML2 viduals (Lyarskaja 1986). Specimen LDM 67/39 shows very unusual feature, which have not PVL CV2 been mentioned by Lyarskaja (1986): the Nu is fused with the Pp (Fig. 30C). MM3 The Pn is broad, L/B index 70-83, 76 on the CV3 ML4 average. The lateral division of the Pn is relative- T ly broad and is composing 33-52% of the general breadth of a plate. The middle pit-line groove (mp) always present. FIG. 31.— Bothriolepis evaldi Lyarskaja, 1986; A, holotype, the The Pmg is broad with the lateral margins articulated head-shield, trunk armour and pectoral fins LDM 67/86 in dorsal view; B, articulated head-shield, trunk armour, longer than the median margins (Lyarskaja left pectoral fin and CD1 LDM 67/3 in ventral view, with dotted 1986). space showing the matrix. Kalnamuiža 1 locality at Amula River, Latvia. Ogre Formation. Abbreviations: ADL, anterior dorso- The sclerotic ring is preserved in some speci- lateral plate; AMD, anterior median dorsal plate; AVL, anterior mens. Its features seem to be similar to that of ventro-lateral plate; CD1-3, dorsal central plates 1-3; CV1-3, ventral central plates 1-3; La, lateral plate; ML2-4, later- the ring of Bothriolepis canadensis (see Stensiö al marginal plates 2-4; MM1, 3, mesial marginal plates 1, 3; 1948) or B. hydrophila (see Miles 1968). MxL, mixilateral plate; Nu, nuchal plate; Pi, pineal plate; PMD, posterior median dorsal plate; Pmg, postmarginal plate; The Sm (extralateral) plate is always badly pre- Pn, paranuchal plate; Pp, postpineal plate; Prm, premedian served. It seems to be relatively long and narrow plate; PVL, posterior ventro lateral plate; Ro, rostral plate; SCLR1, 2, plates 1 and 2 of sclerotic ring; Sm, submarginal plate; (Lyarskaja 1986). T, terminal plate; csl, central sensoty line; dlg1, 2, anterior and The trunk-armour is broad (Lyarskaja 1986), posterior oblique dorsal sensory line grooves; socc, supraoccipital cross-commissural pit-line groove. Scale bar: 5 mm. B/L index 87-99, 95 on the average (n = 10). It is

542 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

relatively high, with a lateral wall 2.5 times as is restricted to half the length of the antero- long as high; the dorsal wall is moderately dorsal margin as in Remigolepis (Stensiö, 1931). arched with well-defined median dorsal ridge. The posterior oblique sensory line groove (dlg2) Length of the dorsal wall, probably, reaches in some cases terminates in some distance from about 50 mm. The shape and proportions of the the lateral margin, but usually the dorso-ventral ventral wall are similar to that of Bothriolepis pit-line groove (dxp) crossing the dorso-lateral prima (see Lyarskaja 1986); B/L index 43-48. ridge is present (Lyarskaja 1986). Anterior margin of the AMD is 1.1-1.6 time as The AVL is broad, the ventral lamina is 1.4-1.7 long as the posterior margin. The antero-lateral time as long as it is broad. The subcephalic divi- corner, postnuchal notch (npn) and the postle- sion 26-33% of total length of the ventral lamina. vator processes (pr.pl) are well-defined, as are The ventral lamina 2.2 times as broad as the later- the obtuse lateral and postero-lateral corners al lamina high in LDM 67/13 (Fig. 30E). The lat- (Lyarskaja 1986). The posterior division of the eral lamina is moderately high, about twice as lateral margin is 1.6-2.5 (2.2 on the average) long as it is high. Ventro-lateral ridge is well-de- times shorter than the anterior division. The ter- fined. The axillary foramen is rather large and gal angle (dma) is situated in between the anteri- slightly elongated in shape (Lyarskaja 1986). or third and middle of the plate and is The PVL has similar proportions to the AVL, as well-marked, the median dorsal ridge (dmr) is in most Bothriolepis species. It is of moderate strongly developed (Lyarskaja 1986). Overlap breadth, the ventral lamina is 2-2.3 times as long areas for ADL and MxL are developed as usual- as it is broad. The subanal division is relatively ly in Bothriolepis in small individuals, but in narrow (Lyarskaja 1986) and occupies 20-27% specimens of medium size the overlap area for of the total PVL length. The lateral lamina is MxL is developed as in Remigolepis (Lyarskaja relatively high, 1.9-2.2 times as long as it is high. 1986). The anterior oblique dorsal sensory line The ventral lamina is 1.3-1.5 time as broad as the grooves (dlg1) are well-defined on the plates of lateral lamina high. The ventro-lateral ridge is small individuals. The posterior oblique dorsal well-developed. sensory line grooves (dlg2) are also well-defined The length/ breadth index of the MV is 1.1 in (Lyarskaja 1986). LDM 67/54. The PMD is arched, moderately broad, B/L The pectoral fin is represented mostly by articu- index 88-105, 95 on the average. The width of lated bones. The proximal segment is about 1.9 the anterior margin comprises 44-55% of total time longer than the distal segment. Both seg- breadth (50% on the average). The median dor- ments bear small lateral and mesial spines in sal ridge is strongly developed (Lyarskaja 1986). small individuals. Individuals of medium size The ADL is slightly longer than the MxL in ar- have the proximal segments bearing prominent ticulated armour. The dorsal lamina is moderate- lateral spines, which are fused in their base ly broad, its breadth exceeds height of the lateral forming well-defined crest. The proximal seg- lamina. The dorso-lateral ridge (dlr) is well- ment is of moderate breadth, 3.3-4 (3.6 on the defined (Lyarskaja 1986). The postnuchal orna- average) times as long as it is broad. The CD1 is mented corner (pnoa) is sharp, long and narrow. with L/B index varying from 2.7 to 3.3, 3 on the The dorsal lamina of the MxL is moderately average. The CV1 is slightly longer than the broad, 1.4-1.6 time as long as it is broad. The CD1 and have similar proportions. The ML2 is dorsal lamina is 1.6-2.2 times as broad as the lat- 4.2-4.6 (4.4 on the average) as long as it is broad. eral lamina is high. Dorsal and lateral laminae The distal segment shows CD3 and CD4, it is enclosing an angle about 126°. The lateral lami- long and relatively narrow. na is moderately high, 2.4-3.2 times as long as it The ornamentation is typically reticulate, is broad. The dorso-lateral ridge is well-defined becoming slightly coarser and sparser in medium- (Lyarskaja 1986). The overlap area for the AMD sized individuals. The network of anastomosing

GEODIVERSITAS • 2001 • 23 (4) 543 Lukševičs E.

ridges are broken into shorter ridges along the Smallest AMD of B. maxima PIN 89/4 is margins of the plates. The ornamentation of the 104 mm long and shows only gently defined pectoral appendage is reticulate in general, on dmr. The largest (33.3 mm long) head-shield of the CD1 the ornament is radially arranged, on B. evaldi LDM 280/1 possess the preorbital the distal segment it consists of longitudinal recess of simpe type, but smallest (97 mm long) gently defined ridges. The T has almost smooth head-shield of B. maxima LDM 84/67 has trifid surface. preorbital recess. Specimens from Kaibala site are important because they lead to evaluate two REMARKS hypothese: 1) B. evaldi does not comprise juve- The following account is the first full treatment niles of the larger, contemporaneous species in English, which supplements Lyarskaja’s B. maxima, which occurs with B. evaldi in the description (in Russian) of Bothriolepis evaldi Ogre Formation; or 2) shape of the preorbital (1986), adding some details. It is based on speci- recess changes dramatically during ontogeny. mens from Lyarskaja’s collection from the type Resemblances and differences between these locality, kept at the Latvian Museum of Natural two species as they have been described by History, and material from the Kaibala site, Lyarskaja (1986) could be explained mostly by gathered by the author. allometric pattern of growth. B. evaldi can be distinguished readily from DISCUSSION B. obrutschewi (Karatajūte-Talimaa 1966), Most part of materials on Bothriolepis evaldi B. cellulosa (Gross 1942) and B. panderi, other from the type locality shows the following fea- Frasnian Bothriolepis representatives from the tures, which can be considered to indicate Main Devonian field. immature individuals: 1) the proportionally B. evaldi resembles B. prima from the Main large orbital fenestra; 2) the breadth of the Prm; Devonian field and B. hydrophila (Miles 1968) 3) the shape of the Pp with strongly convex from Scotland by several features. B. evaldi dif- anterior margin; 4) the relatively broad lateral fers from B. prima in its 1) relatively smaller division of the Pn; 5) the poor development of orbital fenestra; 2) shape of the Prm; 3) strongly the median ventral ridge on the visceral surface developed median dorsal ridge; 4) shape of the of the AMD; 6) the strong development of the postlevator cristae on the visceral surface of the dorsal median ridge; 7) the presence of the ante- AMD. B. evaldi differs from B. hydrophila in its rior oblique dorsal sensory line groove and 1) smaller size; 2) much broader dorsal wall of dorso-ventral pit-line groove. However the the trunk-shield; 3) shape and proportions of largest specimens from the Kaibala locality seem the AMD; 4) shape of the postnuchal ornamented to be from well-grown individuals. B. evaldi corner of the ADL; 5) narrower ventral wall of resembles B. maxima by many features: the trunk-shield; 6) shorter proximal segment of 1) broad Nu; 2) shape and proportions of the the pectoral fin. AMD and ADL; 3) shape of the postnuchal ornamented corner of the ADL; 4) situation of the tergal angle, etc. Nevertheless, B. evaldi dif- Bothriolepis leptocheira Traquair, 1893 fers from B. maxima in its 1) much smaller size; (Figs 32-39) 2) shape of the preorbital recess; 3) shape and proportions of the PMD; 4) strongly developed Pterichthys major – Geikie 1869: 12-13 (after Miles dorsal median, dorso-lateral and ventro-lateral 1968). ridges. The largest AMD from the Kaibala local- Bothriolepis major Ag. – Traquair 1888: 510 (after ity LDM 280/8 which is about 50 mm long and Miles 1968). seem to be from well-grown individual, retain Bothriolepis leptocheirus Traquair, 1893: 285-286. — the strongly developed dorsal median ridge. Stensiö 1931: 164.

544 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

A B

A, C-F C E

D F

FIG. 32. — Bothriolepis leptocheira curonica Gross, 1942; A, head-shield LDM 15/32; B, head-shield LDM 98/12; C, D, head-shield LDM 98/108 in dorsal and visceral views; E, head-shield LDM 98/86; F, head-shield LDM 89/1; A, Imula River near Bienes hamlet, Latvia; B-F, Amula River upstream Kalnamuiža watermill, Latvia. Eleja Formation. Scale bars: 10 mm.

Bothriolepis leptocheira Traquair – Evans in Miles For a full list of synonyms before 1965 see Miles 1968: 112. (1968).

Bothriolepis curonica Gross, 1942: 420, 421, abb. 10. TYPE SPECIMEN. — Gross (1932: 26) selected the — Stensiö 1948: 615. — Lukševičs 1987: 90, text- AVL plate RSM 1859.33.19A as a lectotype illustrated figs 1-6. by Traquair (1906: pl. 29, fig. 3).

GEODIVERSITAS • 2001 • 23 (4) 545 Lukševičs E.

A D C cr.pto

sot

cr.tv cr.o E

soc ifc1 B Prm ifc2

La cir F Pp csl Pmg

Pmg Pn

Nu Pn ifc1

mp socc nm mp socc nm

FIG. 33. — Bothriolepis leptocheira curonica Gross, 1942; A, B, head-shields in dorsal view; A, LDM 98/12; B, LDM 98/86; C-E, Nu; C, D, LDM 98/20 in visceral and dorsal views; E, LDM 98/13 in dorsal view; F, articulated Pn and Pmg LDM 98/18 in dorsal view. Amula River upstream Kalnamuiža watermill, Latvia. Eleja Formation. Abbreviations: La, lateral plate; Nu, nuchal plate; Pmg, postmarginal plate; Pn, paranuchal plate; Pp, postpineal plate; Prm, premedian plate; cir, semicircular pit-line groove; cr.o, median occipital crista; cr.pto, postorbital crista; cr.tv, transverse nuchal crista; csl, central sensory line groove; ifc1, principal section of infraorbital sensory line; ifc2, branch of infraorbital sensory line diverging on La; mp, middle pit-line groove; nm, obtected nuchal area; soc, anterior section of the supraorbital sensory line; socc, supraoccipital cross-commissural pit-line groove; sot, supraotic thickening. Scale bar: 10 mm.

MATERIAL EXAMINED. — Apart from the British Upper Old Red Sandstone. In western Latvia, it has material (Miles 1968), LDM 15/33 (AMD, PMD), been collected in the right bank of Imula River near 15/34, 15/121, 65/110-118, 121, 123, 130, 133, 89/1- Bienes hamlet (number 3 in Fig. 1); stratotype of the 15, 89/27, 89/28, 98/1-68, 98/76-89, 98/91,98/94-101: Amula Formation and exposure of dolomite marls, articulated head-shields and pectoral appendages, dis- clays and siltstones of the Eleja Formation at the right articulated plates of the trunk-armour and pectoral bank of Amula River 1 km upsteam from water-mill fin. All these specimens come from Latvia. Kalnamuiža (number 6 in Fig. 1); the Purviņi Member LOCALITIES AND HORIZON. — The type locality is of the Eleja Formation, lowermost upper Famennian. Bracken Bay, Ayrshire (Heads of Ayr), Scotland; the A possible new subspecies of B. leptocheira occurs in

546 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

the Malyutka Formation of Severnaya Zemlya, out- ifc1 soc crops along Matusevich River (Lukševičs 1999a). alc DIAGNOSIS. — Rather large Bothriolepis with a medi- Prm an dorsal armour length of at least 240 mm. B/L index of dorsal wall of trunk-armour about 77. B/L index of ifc2 the head-shield of 130. Preorbital recess of trifid type. La Anterior margin of the head-shield is rounded. cir Orbital fenestra is relatively small. Prm broad, orbital margin is much shorter than rostral margin. Nu L/B csl index of 84, with very short orbital facets. Pp Supraoccipital groove long, sometimes fused with a Nu Pmg long middle pit-line. AMD relatively narrow, B/L index 83, with the relatively short anterior margin. Pn PMD broad with narrow anterior margin. Median dorsal ridge poorly developed in posterior part of mp PMD. Dorso-lateral and ventro-lateral ridges are d.end mppr socc nm well-marked. Both AVL and PVL are elongated.

Proximal segment of the pectoral appendage is long FIG.34.— Bothriolepis leptocheira curonica Gross, 1942, at- and slender, 5.5 times as longs as it is broad. tempted reconstruction of the head-shield, based on LDM 89/1. Ornamentation is fine and basically of reticular type, Amula River upstream Kalnamuiža watermill, Latvia. Eleja in quite large individuals becoming smooth. Formation. Abbreviations: La, lateral plate; Nu, nuchal plate; Pmg, postmarginal plate; Pn, paranuchal plate; Pp, postpineal plate; Prm, premedian plate; alc, antero-lateral angle of head- shield; cir, semicircular pit-line groove; csl, central sensory line DESCRIPTION groove; d.end, opening of canal for endolymphatic duct; ifc1, principal section of infraorbital sensory line; ifc2, branch of This species is well-represented in clay of the infraorbital sensory line diverging on La; mp, middle pit-line Kalnamuiža locality by many articulated skulls, groove; mppr, posterior process on Nu; nm, obtected nuchal area; soc, anterior section of the supraorbital sensory line; socc, some articulated proximal segments of the pec- supraoccipital cross-commissural pit-line groove. Scale bar: 10 mm. toral fin, as well as disarticulated plates of the trunk-shield and pectoral appendage. Most are from individuals of moderate size. The plates are with the lateral horns less extended laterally usually flattened, often deformed. The head- than that in B. maxima or B. gigantea, and more shield is moderately broad, with average B/L broad at their base. The orbital edges of the Prm index 130 (n = 10), slightly narrower than the and La are not thickened (this feature is not seen head-shield (B/L index 142) restored by Miles in Scottish material). The antero-lateral corners (1968); the differences in breadth could be of otico-occipital depression on the visceral explained by difficulties in restoration of a cor- surface of the head-shield extend forward so rect shape and proportions of the head-shield that they end just in front of the transverse plane from disarticulated plates. As in Scottish materi- of the anterior margin of the orbital fenestra, as al, the rostral margin is convex, rounded, usually in Scottish material (Miles 1968: 76). slightly longer than the posterior margin. The The Prm is weakly arched, with B/L index 123- head-shield is weakly vaulted both rostrocau- 148, broader than Prm in Scottish material dally and transversely, as in Scottish material, (Miles [1968] has mentioned B/L index of 114, but the anterior part of the Prm and La is 120 and 128). The rostral margin is convex, it is strongly curved. The antero-lateral corner (alc), three times longer than the slightly concave the prelateral notch and the lateral process are orbital margin in material from both countries weakly defined, not seen in dorsal view. The (for comparison see Figs 32-34 and Miles 1968: orbital fenestra is relatively small, with a B/L pl. 20, figs 1, 2). Also such characters as the posi- index varying from 175 in individuals of moder- tion of the infraorbital sensory groove (ifc1) ate size to 150 in largest individuals. The preor- which crosses the plate close to its rostral mar- bital recess both in Latvian and Scottish material gin, and a well-defined anterior section of the (Miles 1968: text-fig. 36) is of trifid type, but supraorbital sensory line (soc), are similar.

GEODIVERSITAS • 2001 • 23 (4) 547 Lukševičs E.

B, C

FIG. 35. — Bothriolepis leptocheira curonica Gross, 1942; A, AMD LDM 15/121, Imula River near Bienes hamlet, Latvia. Eleja Formation; B, AMD LDM 98/21; C, PMD LDM 98/36. Amula River upstream Kalnamuiža watermill, Latvia. Eleja Formation. Abbreviations: AMD, anterior median dorsal plate; PMD, posterior median dorsal plate. Scale bars: 10 mm.

The La “is of the short, broad type” (Miles 1968: general breadth of a plate. Long supraoccipital 77). The L/B index of the La of 120-128, 124 on groove (socc) usually is present in Latvian mate- the average in Latvian material. The Pp has L/B rial, it terminates usually at the level of the mid- index varying from 69 to 83, it is elongated in dle of the plate posterior margin. The middle both material from Scotland (Miles 1968: pl. 20, pit-line groove (mp) is always present, some- fig. 4) and Latvia, e.g., LDM 89/1 (Fig. 34). times it is very long (LDM 98/86, Fig. 33B) or The Nu has the L/B index about 84 (Miles men- (LDM 98/3, 7, 12, 89/5, Fig. 33A) it fuses with tions L/B index 83). The plate is always broadest the supraoccipital groove. This character was across the lateral corners. The anterior division not described or drawn by Miles (1968: text- of the lateral margin is usually convex (RSM fig. 36) and not clearly seen in his illustrations; 1859.33.632A and B, LDM 98/12, 13, 20, 86, however RSM 1859.33.632B shows long Fig. 33, etc.), and a little shorter than the poste- supraoccipital groove and the middle pit-line rior division. groove also on the Pn (pers. obs.). The Pn is of moderate breadth, L/B index about The trunk-armour is narrow, relatively low, 86, Miles (1968) has restored it with L/B index with rather flattened low dorsal wall and the lat- of about 80. The lateral division of the Pn is eral wall more than three times as long as high. relatively narrower than in B. ciecere and is Length of the dorsal wall, probably, is more composing 34-45% (38.7 on the average) of the than 240 mm (Miles [1968] estimated the dorsal

548 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

A n.prpl pnoa pr.pl oa.AMD

npl B

pro oa.AVL dlg2 dlr lcg

oa.MxL d B, D dlg2 C oa.PMD A, C

oa.PMD D cf.AMD

oa.ADL

cf.MxL

oa.PVL dlr pt2

FIG. 36. — Bothriolepis leptocheira curonica Gross, 1942; A, AMD LDM 98/21 in dorsal view; B, ADL LDM 98/58; C, MxL LDM 98/53; D, PMD LDM 98/35 in visceral view. Amula River upstream Kalnamuiža watermill, Latvia. Eleja Formation. Abbreviations: ADL, anterior dorso-lateral plate; AMD, anterior median dorsal plate; MxL, mixilateral plate; PMD, posterior median dorsal plate; cf.AMD, area overlapping AMD; cf.MxL, area overlapping MxL; d, dorsal corner; dlg2, posterior oblique dorsal sensory line groove; dlr, dorso-lateral ridge; dmr, dorsal median ridge; l, lateral corner; lcg, main lateral line groove; npl, postlevator notch; n.prpl, notch in dorsal margin of ADL for external postlevator process of AMD; oa.ADL, area overlapped by ADL; oa.AMD, area overlapped by AMD; oa.AVL, area overlapped by AVL; oa.MxL, area overlapped by MxL; oa.PMD, area overlapped by PMD; oa.PVL, area overlapped by PVL; plc, postero-lateral corner; pnoa, postnuchal ornamented corner; pro, processus obstans of trunk armour; pr.pl, external postlevator process; pt2, posterior ventral pit. Scale bars: 10 mm. wall reached a length of some 140 mm). The antero-lateral and lateral corners, and the ventral wall is narrow, with B/L index about 53 postlevator processes (pr.pl) are well-defined in Latvian material. The subcephalic and subanal (Miles 1968: text-fig. 37; Fig. 35A). The poste- divisions are relatively long. rior division of the lateral margin is 1.4- The AMD is weakly arched, narrow, B/L 1.6 time shorter than the anterior division. index about 83 in Latvian material, and about There is no median dorsal ridge neither in 77 in Scottish material (Miles 1968: 78). The Scottish, nor in Latvian material.

GEODIVERSITAS • 2001 • 23 (4) 549 Lukševičs E.

ABD

B-G

FIG. 37. — Bothriolepis leptocheira curonica Gross, 1942; A, ADL LDM 98/58; B, ADL LDM 89/12; C, ADL LDM 98/94; D, MxL LDM 98/54; E, MxL LDM 89/2; F, AVL LDM 89/7; G, AVL LDM 98/30. Amula River upstream Kalnamuiža watermill, Latvia. Eleja Formation. Abbreviations: ADL, anterior dorso-lateral plate; AVL, anterior ventro-lateral plate; MxL, mixilateral plate. Scale bars: 10 mm.

The PMD is broad in comparison with the postnuchal ornamented corner (pnoa) is large in AMD, B/L index about 95 in material from all studied specimens. Scotland (Miles 1968) and varies from 88 to 101, The MxL was not described by Miles (1968) in 95 on the average, in material from Latvia. The details as being represented in Scottish material anterior margin is very narrow, convex and only by poorly preserved specimens. However, rounded; the posterior margin is well convex, 2- the dorsal lamina of the plate was correctly 2.5 times longer than the anterior margin; it is assumed by Miles (1968: 78) being slightly less without pronounced posterior corner (Miles than twice as long as it is broad. The dorsal cor- 1968: text-fig. 38; Fig. 35C; 36D). ner is clearly seen. The lateral lamina is low, The dorsal lamina of the ADL is of moderate more than three times as long as it is broad. The breadth, 3.5 times as long as it is broad in RSM posterior oblique sensory line groove (dlg2) 1859.33.632D (Miles 1968: pl. 20, fig. 3) or a lit- usually terminates in some distance from the lat- tle broader in LDM 98/58 (Figs 36B; 37A). The eral margin; LDM 98/53 shows dlg2 crossing

550 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

CBA

A-D, F, G

FIG. 38. — Bothriolepis leptocheira curonica Gross, 1942; A, AVL in visceral view with articulated proximal segment of pectoral fin LDM 98/78; B, PVL LDM 98/45; C, PVL LDM 98/41; D, ML2 LDM 98/76; E, distal segment of the pectoral fin LDM 89/4; F, CV1 LDM 98/90; G, CV1 LDM 98/77. Amula River upstream Kalnamuiža watermill, Latvia. Eleja Formation. Abbreviations: AVL, anterior ventro- lateral plate; CV1, ventral central plate 1; ML2, lateral marginal plate 2; PVL, posterior ventro lateral plate. Scale bars: 10 mm.

the dorso-lateral ridge. In small specimen LDM defined corners (Miles 1968: 79, text-fig. 39A; 98/54 the dlg2 is connected with the main lateral Figs 37F, G; 38A). The subcephalic division line groove (lcg). The dorso-lateral ridge (dlr) is comprises 21-25% (22.5 on the average) of total well-defined both in the ADL and MxL in length of the ventral lamina (about 20% in material from Latvia; Miles (1968) claimed that Scottish material: Miles 1968). The lateral lamina “there is no clear development of the dlr on is not preserved within the material from either the MxL or ADL”; in fact dlr is not Scotland. It is low, the ventral lamina 3.8 times clearly seen, particularly in MxL, because of as broad as the lateral lamina high in LDM preservation of the Scottish material as internal 98/30. The lateral lamina is low. The right AVL impressions. overlaps the left AVL by very narrow overlap The AVL with the ventral lamina is 1.9-2 times area. as long as it is broad; the anterior margin of the The PVL has variable proportions. It is relative- ventral lamina is rounded without clearly ly narrow, the ventral lamina is 2.4-2.7 times as

GEODIVERSITAS • 2001 • 23 (4) 551 Lukševičs E.

d dlg2 A oa.PMD DB

cit2

CD1

oa.ADL lcg oa.PVL dlr oa.AVL cf.AVL C D, E

cf.MV E ML2

cf.PVL

MM2

A-C

dc oa.PVL vlr CD2

FIG. 39. — Bothriolepis leptocheira curonica Gross, 1942; A, MxL LDM 89/2; B, AVL plate in visceral view with articulated proximal segment of the pectoral fin in dorsal view LDM 98/78; C, PVL LDM 98/45 in ventral view; D, CV1 LDM 98/90; E, distal segment of the pectoral fin LDM 89/4. Amula River upstream Kalnamuiža watermill, Latvia. Eleja Formation. Abbreviations: ADL, anterior dorso-lateral plate; AVL, anterior ventro-lateral plate; CD1, dorsal central plate 1; CD2, dorsal central plate 2; CV1, ventral central plate 1; ML2, lateral marginal plate 2; MM2, mesial marginal plate 2; MV, median ventral plate; MxL, mixilateral plate; PMD, posterior median dorsal plate; PVL, posterior ventro lateral plate; cf.AVL, area overlapping AVL; cf.MV, area overlapping MV; cf.PVL, area overlapping PVL; cit2, transverse thickening on the visceral surface of AVL; cu, postero-ventral ornamented corner; d, dorsal corner of MxL; dc, dorsal corner of lateral lamina of PVL; dlg2, posterior oblique dorsal sensory line groove; dlr, dorso-lateral ridge; lcg, main lateral line groove; oa.ADL, area overlapped by ADL; oa.AVL, area overlapped by AVL; oa.PMD, area overlapped by PMD; oa.PVL, area overlapped by PVL; vlr, ventro-lateral ridge. Scale bars: 10 mm. long as it is broad. The subanal division is nar- The MV is not known, but the shape of the row, it occupies about one fifth-one third (22- AVL and PVL suggest the small size of the 32%) of the total PVL length (Miles 1968: 80; slightly elongated MV. Figs 38B, C; 39C). The lateral lamina is moder- The pectoral fin is represented in Latvian mate- ately high, 2.3-2.7 times long as it is high. The rial by some disarticulated bones, and six speci- ventro-lateral ridge (vlr) is clearly defined both mens showing articulated plates of the proximal in the AVL and PVL. segment associated with the AVL. The proximal

552 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

segment bears small rarely set lateral and mesial by Sorokin & Lyarskaja in 1975, and expedi- spines, the lateral spines are larger than the tions of the Latvian Museum of Natural History mesial ones; Miles (1968) suggested the mesial in 1981-1982 in the Kalnamuiža locality. Later spines perhaps absent. The proximal segment is specimens described by Gross (1942), as well as very long and narrow, it is 4.8-6 (5.5 on the a newly collected material from Kalnamuiža site average) times as long as it is broad (5.5 to were briefly described and figured (Lukševičs 6 times as long as broad in Scottish material: 1987), stressing the close morphological resem- Miles 1968: 80). The CD1 is of moderate size blance of B. curonica with B. leptocheira from with L/B index varying from 2.7 to 3.7 (3.3 on Scotland. A direct comparison of the specimens the average). The CV1 is gently longer than the belonging to these species during preparation of CD1 and slightly more elongate (L/B 3.4). The this work has indicated that they are conspecific. CD2 is slightly longer than it is broad. Specimen Nevertheless, there are several features which LDM 89/4 is an articulated distal segment. It is suggest than the Latvian material is a new sub- not adorned with marginal spines, the lateral species of Bothriolepis leptocheira. Bothriolepis spines are sharp and proximally directed. The leptocheira curonica Gross, 1942 is morphologi- distal segment is very long and narrow, L/B cally very close to Bothriolepis leptocheira index 5.7. The CD5 plate is present in material leptocheira from Scotland (Miles 1968). B. lep- from both countries. tocheira curonica differs from the nominal sub- The ornamentation is fine and basically of the species in its 1) larger size; 2) more elongated reticular type (Miles 1968: 80), in quite large AVL; 3) smoother ornamentation. The diagno- individuals from Latvia becoming smooth. The sis of the species presented here is to the large network of anastomosing ridges are broken into extent based on that provided by Miles (1968), radially arranged shorter ridges on the head- and description adds some previously not shield plates. On the posterior margin of the known details and comprises comparison of the PMD, subcephalic and subanal divisions the material from Latvia with that from Scotland. anastomoses between the ridges reduce and nodose short ridges are present. The ornamenta- DISCUSSION tion of the pectoral appendage is reticulate in Within other Bothriolepis from Scotland, Baltic general, on the anterior part of the CD1 and and Russia, Bothriolepis leptocheira is particu- CV1 the ornament is radially arranged; in the larly characterized by a very short orbital mar- distal part of the proximal segment the orna- gin of the Prm, the long and narrow AMD and mentation became smooth. The longitudinal slender pectoral appendage (Miles 1968). lineation in the ornament of the distal segment is Among the other species of Bothriolepis, B. lep- well shown in LDM 89/4. tocheira is morphologically closest to B. jarviki Stensiö, 1948 from Greenland (Stensiö 1948). REMARKS Both species are similar in 1) their size; 2) shape This species was established by Traquair (1893) and proportions of La and Nu of the head- and well-described by Stensiö (1948) and Miles shield; 3) the shape and proportions of the (1968). Gross (1942) erected Bothriolepis curonica AMD; 4) the slender pectoral fin. However, as a new species from Latvia based on a slightly B. jarviki differs from B. leptocheira in the other damaged head-shield LDM 15/32, two AMD shape and proportions of the Prm, Pp, Nu, and one PMD, and several fragments of pectoral PMD and the ornamentation. B. leptocheira fin bones collected in 1934 in the Bienes locality closely resembles also B. jeremejewi Rohon, by student of geology Melderis. This descrip- 1900 from Timan by 1) the slender pectoral tion was repeated by Stensiö (1948) in Addenda appendage; 2) the shape and proportions of the to his monograph without further comments. PMD; 3) smooth reticulate ornamentation. Since then, the remains of this fish were collected Unfortunately, B. jeremejewi is poorly described

GEODIVERSITAS • 2001 • 23 (4) 553 Lukševičs E.

and known species, represented in collections of of moderate breadth, with B/L index about 112, ros- LDM and PIN by some badly preserved speci- tral margin 1.7-1.9 times longer than orbital margin. Nu arched, narrow, with L/B index of 83. Pn narrow. mens showing disarticulated fragments of the B/L index of dorsal wall of trunk-armour about 82. PMD and pectoral fin. There is not yet enough Median dorsal ridge poorly developed. AMD moder- information to decide whether these species are ately narrow, B/L index about 79-88. Anterior closely related or not. margin of AMD short and concave. PMD narrow, B/L index about 75-89, 82 on average. ADL with narrow lateral lamina and large postnuchal ornamented corner. Axillary foramen long and narrow. Proximal Bothriolepis ornata Eichwald, 1840 segment of the pectoral appendage moderately long, (Figs 40-54) four times as long as broad. Ornamentation typically reticulate, in quite large individuals becoming coarser Bothriolepis ornatus Eichwald 1840: 78. and sparser. Bothriolepis prisca – Eichwald 1840: 425. Bothriolepis ornata – Eichwald 1860: 1513, pl. cvi, DESCRIPTION fig. 3. Bothriolepis ornata is well-represented at the Asterolepis ornata – Eichwald 1861: 448 (p.p.). locality at the right bank of Skujaine River Bothriolepis cf. ornata Eichw. – Gross 1942: 403, 422 1 km E from Klūnas hamlet by many disartic- (p.p.) [non text-fig. 11]. ulated plates and some articulated skulls. Most For full list of synonyms before 1932, see Gross are from well-grown individuals of moderate (1932). size, but there are also some small, and quite TYPE SPECIMEN. — Woodward (1891) selected MM large specimens. Bothriolepis ornata is one of 116/107 as the lectotype (Eichwald 1860: 1513, pl. the largest of species of Bothriolepis, but did CVI, fig. 3). It is an AMD, collected by Helmersen. not quite reach the size of B. maxima or MATERIAL EXAMINED. — From the type locality at B. gigantea. The head-shield (Figs 40A-C; Priksha River: MM 5/198, PVL; BMNH P.4600, 42A, B) has a B/L index of about 127, and is ML1, P.710, MxL; PIN 835/4, Nu. From the locality at Skujaine River near Klūnas hamlet: LDM 43/730, strongly vaulted both rostrocaudally and 100/1-65, 145-147, 336, 346, 354-368, 396-426, 441, transversely. The rostral margin is convex, 523, 525-527, LGI 5/2045-2078, two articulated head- slightly shorter than the posterior margin, shields and their fragments, disarticulated plates of which is weakly convex and bears a well- the head-shield, trunk-armour and pectoral appendage; PIN 1491/89, ADL, 1491/90-95, two Pn, defined posterior median process. There are two Sm, Pmg, CD2. well-defined anterolateral corners (alc) and a

LOCALITIES AND HORIZON. — The type locality is the deep prelateral notch (nprl). The obtected exposure at Priksha River, Russia; the upper nuchal area (nm) is long, extending onto the Famennian Lnyanka Beds. Other studied material Pn, it is broadest on the Nu. The orbital fen- comes from the two outcrops of white and pink sand estra is relatively short and broad (B/L index containing abundant fish bones, dolomite marl and marl at the right bank of Skujaine River down Klūnas about 200). Preorbital recess (prh) is distinctly village, Latvia; the Famennian Tērvete Formation. trifid with extended lateral horns and a point- Studied fragments of plates, undescribed here, which ed median division, as in B. maxima and comes from Msta River near Beryozovik village (kept B. hayi Miles, 1968. The median division at IEC), and those reported from Belaya, Lnyanka and Mshanka Rivers in Novgorod region reached the middle of Prm, but lateral horns (Ostrometskaya & Kotlukova 1966; Obruchev 1964) did not reach the middle of La, as is the case and the North Timan, the Pokayama Formation in B. hayi. The orbital edges of the Prm and La (Obruchev 1958), probably also belong to B. ornata. are thickened, as in B. ciecere, B. macphersoni DIAGNOSIS. — Rather large Bothriolepis with the dor- and B. karawaka. sal length of the trunk-armour reaching 230-240 mm The visceral skull surface (Fig. 40B) shows the and the length of the head-shield at least 100 mm. B/L index of head-shield 127. Preorbital recess of trifid broad otico-occipital depression which is well- type. Orbital edges of Prm and La are thickened. Prm defined by the paramarginal cristae. The antero-

554 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

A BF

C DE A-C, F-K

M K

D, E, L, M

FIG. 40. — Bothriolepis ornata Eichwald, 1840; A, B, head-shield LDM 100/31 in dorsal and visceral views; C, head-shield LDM 100/32 in dorsal view; D, E, La LGI 5/2053 in dorsal and visceral views; F, La LDM 100/44; G, H, Nu LDM 100/42 in dorsal and visceral views; I, Nu LDM 100/39; J, Nu LDM 100/38; K, Nu LDM 100/399; L, articulated Nu and Pp LDM 100/398; M, Pn LDM 100/402. Skujaine River near Klūnas village, Latvia. Tērvete Formation. Abbreviations: La, lateral plate; Nu, nuchal plate; Pn, paranuchal plate; Pp, postpineal plate. Scale bars: 10 mm. lateral corner of otico-occipital depression is lateral corner is rounded and does not extend broad in its base and extended nearly to the ros- laterally over the middle of the Pn’s posterior tral margin of the orbital fenestra. The postero- margin, as it does in B. ciecere. The transverse

GEODIVERSITAS • 2001 • 23 (4) 555 Lukševičs E.

A tal crista is relatively low, often it consists from several small ridges. The transverse nuchal crista is prominent. The median ridge (mr) sharing the broad paired pits (g) of Pp plate is broad and anteriorly bears a tubercle. The supraotic thickening on the Nu is very low. The Prm (Fig. 42C-E) is broadest slightly posteriorly from the infraorbital sensory groove. The rostral margin is convex, the orbital margin is straight or weakly concave and bears clearly defined but shallow nasal notch (pnn). The infraorbital sensory groove (ifc1) crosses the plate anteriorly from its middle part. The shape B and proportions of the Prm resemble that in B. ciecere, differing well from that in such taxa as B. leptocheira and B. maxima. The La (Figs 40D-F; 41; 43F) is moderately broad with L/B index about 123-139, 132 on the average. The rostral margin is relatively short and almost straight, the antero-median and antero-lateral corners are well-defined. The infraorbital sensory groove (ifc1) crosses the plate in its anterior part not far from the lateral margin. The central sensory line groove (csl) usually finishes slightly anteriorly the middle of C an orbital fenestra length, it might be interrupted or very short. The Pp (Figs 40L; 43A, B) is broad, L/B index varies from 56 to 83. As in other species the anterior margin is strongly convex in small specimens and became almost straight with increasing size. The Nu (Figs 40G-L; 43C-E) is vaulted with an angle between right and left halves about 132°. It is relatively narrow, L/B index 72-93, 83 on the average, and in most aspects resembles that in B. ciecere. The anterior division of the lateral margin usually is concave and equal or a little FIG. 41. — Bothriolepis ornata Eichwald, 1840, La plates; A, B, LDM 100/398 in dorsal and visceral views; C, LDM longer than the posterior division. The posterior 100/525. Skujaine River near Klūnas village, Latvia. Tērvete margin is weakly convex and bears well-defined Formation. Abbreviation: La, lateral plate. Scale bar: 10 mm. median process (prnm). The orbital facetes are short, similarly as in B. leptocheira and lateral groove is moderately broad and clearly B. ciecere. There are short supraoccipital defined. A relatively broad shallow depression grooves (socc), which terminate little in front of anteriorly from the antero-lateral corner of pre- the obtected nuchal area at the external openings orbital recess is the lateral pit, which is situated for the endolymphatic ducts (d.end). Specimen more laterally than mesially. The median occipi- LDM 100/42 (Figs 40G; 43D) shows the broad

556 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

Prm La

Pp D Pmg Nu Pn

mp soc ifc1 B alc ifc2 cir prh prh pnn lpr E

fe.orb csl

nm d.end mppr

FIG. 42. — Bothriolepis ornata Eichwald, 1840; A, restoration of head-shield based on LDM 100/32; B, head-shield LDM 100/31; C- E, Prm; C, D, LDM 100/34 in dorsal and visceral views; E, LDM 100/396 in dorsal view. Skujaine River near Klūnas village, Latvia. Tērvete Formation. Abbreviations: La, lateral plate; Nu, nuchal plate; Pmg, postmarginal plate; Pn, paranuchal plate; Pp, postpineal plate; Prm, premedian plate; alc, antero-lateral angle of head-shield; cir, semicircular pit-line groove; csl, central sensory line groove; d.end, opening of canal for endolymphatic duct; fe.orb, orbital fenestra; ifc1, principal section of infraorbital sensory line; ifc2, branch of infraorbital sensory line diverging on La; lpr, lateral process of head-shield; mp, middle pit-line groove; mppr, posterior process; nm, obtected nuchal area; pnn, nasal notch; prh, preorbital recess; soc, anterior section of the supraorbital sensory line. Scale bar: 10 mm. unornamented area along the postpineal notch, sion is as long as it is broad. The lateral margin which probably was overlapped by the extreme- of the plate is short. The Pn usually bears a short ly broad Pp. As a result the outer surface of this middle pit-line groove (mp). Nu was excluded from contact with the orbital The Sm (extralateral plate) is known from two fenestra, as in Asterolepis. badly preserved specimens PIN 1491/92 The Pn (Figs 40M; 43H-J) with L/B index about (Fig. 43G), and PIN 1491/93, both are the ante- 98. The lateral division of the Pn is relatively rior end of the plate. The dorsal margin has a narrow and composing 50% of the breadth of a prominent antero-dorsal process (ad1). There is median division of the plate. The median divi- a groove (gr.sc) running along the dorsal margin

GEODIVERSITAS • 2001 • 23 (4) 557 Lukševičs E.

ABCmr F

nprl

g ifc2 cir ad2 gr.sc G ad1

ifc1 csl

D E

csl ood sot

cr.tv d.end nm d.end HIcr.o

cr.pm J

ood

cr.tv mp

FIG. 43. — Bothriolepis ornata Eichwald, 1840; A, B, Pp LDM 100/41 in dorsal and visceral views; C-E, Nu; C, LDM 100/38 in dorsal view; D, E, LDM 100/42 in dorsal and visceral views; F, La LDM 100/358 in dorsal view; G, fragmentary Sm PIN 1491/92; H-J, Pn; H, I, PIN 1491/91 in dorsal and visceral views; J, PIN 1491/90 in dorsal view. Skujaine River near Klūnas village, Latvia. Tērvete Formation. Abbreviations: a2Sm, posterior attachment area for submarginal plate; ad1, anterior articular process on submarginal plate; ad2, posterior articular process on submarginal plate; cir, semicircular pit-line groove; cr.o, median occipital crista; cr.pm, paramarginal crista; cr.tv, transverse nuchal crista; csl, central sensory line groove; d.end, opening of canal for endolymphatic duct; g, paired pits on Pp; gr.sc, groove, possible for sensory canal; ifc1, principal section of infraorbital sensory line; ifc2, branch of infraorbital sensory line diverging on La; La, lateral plate; mp, middle pit-line groove; mr, median ridge of Pp; nm, obtected nuchal area; nprl, prelateral notch; Nu, nuchal plate; ood, otico-occipital depression; Pn, paranuchal plate; Pp, postpineal plate; pr.po, antero-lateral corner of otico-occipital depression; Sm, submarginal plate; sot, supraotic thickening. Scale bar: 10 mm. of the ornamented part of the plate, which is The trunk-armour description is based on similar to that of B. obrutschewi (see Karatajūte- plasticine reconstruction composed of large Talimaa 1966) and B. macphersoni. disarticulated plates. The trunk-armour is rela-

558 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

tively low and broad (B/L index 82), and broader than in B. leptocheira or B. ciecere A (B/L index in both species about 77). Length of the dorsal wall probably exceeded 240 mm in largest individuals, but was only 50 mm in the smallest examined specimens. The dorsal wall is of moderate height, with right and left laminae enclosing an angle of about 132°. The median dorsal ridge is weakly defined, the dorsal wall is rounded transversely. The dorso- lateral and ventro-lateral ridges are well- defined, but in quite large individuals slightly rounded. The characteristic feature is that the depression anteriorly the tergal angle is weakly developed as in B. groenlandica Heintz, 1930 B (see Stensiö 1948). The AMD (Figs 44-46) with B/L index about 79-88, 83 on the average. The anterior margin is always concave. It is narrow, usually shorter than the posterior margin, and 2.2-3.1 times narrower as a total breadth of the plate, differing in its proportions from all the other species of Bothriolepis from the Famennian of Baltic area. The antero-lateral and lateral corners are rounded, the postnuchal notch (npn) is deep and postlevator process (pr.pl) is sharply defined. The posterior division of the lateral margin is 1.4-1.6 time shorter than the anterior division. There is no median dorsal ridge. Overlap areas for ADL and MxL are normally developed as usually in Bothriolepis in general, but in large FIG. 44. — Bothriolepis ornata Eichwald, 1840, AMD LDM 100/2; A, dorsal view; B, visceral view. Skujaine River near Klūnas individuals the sutural connection of AMD with village, Latvia. Tērvete Formation. Abbreviation: AMD, anterior MxL is often of Remigolepis type. The overlap median dorsal plate. Scale bar: 10 mm. area for ADL along the postnuchal notch is of wedge type: the outer surface of ADL slightly narrow postlevator thickenings (alr). The overlaps AMD. The anterior oblique dorsal sen- supranuchal area (sna) is well-defined and sory line groove (dlg1) is not present even in broadest at the antero-lateral corners. The ante- smallest specimen, the posterior oblique dorsal rior ventral pit (pt1) is deep. The median ventral sensory line groove (dlg2) is well-defined also ridge (mvr) is high, it divides in the posterior on the plates of rather large individuals. In some third of the plate to form a deep median ventral cases the posterior oblique dorsal sensory line groove (grm). groove is short: specimen LGI 5/2078 The anterior and posterior margins of the PDM (Fig. 46H) shows dlg2 on the left side terminat- (Figs 47-49A, B) both are strongly convex, with ed in front of the postero-lateral margin. a well-developed anterior and posterior corners. The visceral surface of the AMD (Figs 44B; 45B, The lateral and postero-lateral corners are also E; 46F) shows a narrow elongated levator fossa well-defined. The width of the anterior margin (f.retr), which is delineated by the low and varies between 45-63% of total breadth of the

GEODIVERSITAS • 2001 • 23 (4) 559 Lukševičs E.

A-C

EC D

D, E

FIG. 45. — Bothriolepis ornata Eichwald, 1840, AMD; A, B, LDM 100/4 in dorsal and visceral views; C, LDM 100/527 in dorsal view; D, LDM 100/406 in dorsal view; E, LDM 100/405 in visceral view. Skujaine River near Klūnas village, Latvia. Tērvete Formation. Abbreviation: AMD, anterior median dorsal plate. Scale bars: 10 mm.

plate. The PMD is arched with the median dorsal tral pit (pt2) and strongly developed ventral ridge (dmr) well-defined in individuals of small tuberosity (tb) in large individuals (Fig. 48). The size; in large individuals the dmr is rounded. crista transversalis interna posterior (cr.tp) is The suture with the MxL is of wedge type. The low and smoothed, the postmarginal area (pma) median ventral ridge and median ventral groove being narrow. are weakly defined on the visceral surface of the The dorsal lamina (dlm) of the ADL (Figs 49C-E; plate in small individuals and the median ventral 50A-C) is relatively long, but due to significant ridge is rather high with the deep posterior ven- breadth of a strongly pronounced postnuchal

560 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

AB Cnpn D dma pr.pl dlg2

oa.MxL E oa.PMD

FGpr.p sna alr f.retr pt1

mvr

cf.ADL H cf.MxL I

grm

FIG. 46. — Bothriolepis ornata Eichwald, 1840, AMD; A-E, G-I, dorsal views; F, visceral view; A, LDM 100/405; B, LGI 5/2046; C, LDM 100/2; D, holotype MM 116/107; E, F, LDM 100/3; G, LDM 100/4; H, LGI 5/2078; I, LGI 5/2051; A-C, E-I, Skujaine River near Klūnas village, Latvia. Tērvete Formation; D, Prikscha River, Novgorod region, Lyubitino district, Russia. Lnyanka Formation. Abbreviations: ADL, anterior dorso-lateral plate; AMD, anterior median dorsal plate; MxL, mixilateral plate; PMD, posterior median dorsal plate; alr, postlevator thickenings of AMD; cf.ADL, area overlapping ADL; cf.MxL, area overlapping MxL; dlg2, posterior oblique dorsal sensory line groove; dma, tergal angle; f.retr, levator fossa; grm, ventral median groove; mvr, median ventral ridge; npn, postnuchal notch; oa.MxL, area overlapped by MxL; oa.PMD, area overlapped by PMD; prp, posterior process of AMD; pr.pl, external postlevator process of AMD; pt1, anterior ventral pit; sna, supranuchal area of AMD. Scale bar: 20 mm.

GEODIVERSITAS • 2001 • 23 (4) 561 Lukševičs E.

A CD

E F

C-G A, B

B H

FIG. 47. — Bothriolepis ornata Eichwald, 1840, PMD; A, B, LDM 100/354 in dorsal and visceral views; C, D, LDM 100/356 in visceral and dorsal views; E, F, LDM 100/357 in dorsal and visceral views; G, LDM 100/355 in dorsal view; H, LDM 100/528 in dorsal view. Skujaine River near Klūnas village, Latvia. Tērvete Formation. Abbreviation: PMD, posterior median dorsal plate. Scale bars: 10 mm. ornamented corner (pnoa) it is only 2.2 as long broad, with long and sharp postero-ventral as it is broad. The lateral lamina is three times as ornamented corner (cu). long as it is high. The ADL is not simply The AVL (Figs 51A-C; 52D-E) is of moderate overlapped by AVL, but also at the same time breadth, the ventral lamina of the single com- overlaps that plate posteriorly the processus plete plate is 1.5 time as long as it is broad. obstans, as in B. canadensis, B. groenlandica and The subcephalic division is of moderate length, B. maxima. comprises 29% of total length of the ventral The MxL (Figs 49F; 50D-F; 52A) is moderately lamina and has a weakly defined antero-lateral broad. The dorsal lamina of the plate is less than corner (c.al). The right AVL overlaps the left twice (1.7-1.8 time) as long as it is broad. The similar to the other Bothriolepis. The axillary lateral lamina is 2.5-2.6 times as long as it is foramen (f.ax) is rather large and about twice

562 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

as long as it is broad (Fig. 51C). The processus A cf.AMD brachialis shows some features not found in other Bothriolepis from the Main Devonian cf.MxL Field (Fig. 51D). The fossa articularis pectoralis is not boynded off anteriorly by the grm margo limitans. The groove around the external opening of the funnel pit (fp) is deep, its tb dorsal part is divided into two unequal deep pits; the larger and more distally situated pit bears an opening of the canal. Specimen LDM pt2 100/365 (Figs 51D; 52E) shows the funnel pit l divided into two divisions by very thin longitudinal wall. Probably this structure is the result of the joint desease. plc The visceral surface of the AVL (Figs 51A; 52D) cr.tp shows as in most part of other species of prv2 Bothriolepis the high transverse anterior crista pa pma (cit1) running antero-mesially and the low and cf.AMD broad transverse thickening (cit2) directed more B mesially. The PVL (Fig. 49G, H) is of moderate grm breadth, the ventral lamina is twice as long as cf.MxL it is broad. The subanal division is relatively tb narrow, it occupies about 30% of the total PVL length. The lateral lamina is about twice pt2 as long as it is high. Left PVL overlaps the opposite PVL. The MV (Fig. 52B) is more elongated than in most species of Bothriolepis, the L/B index l reaching about 1.4-1.7. The pectoral fin is represented by many disarticulated bones (Figs 52F-I; 53), and two spec- plc imens showing articulated plates of the cr.tp proximal segment associated with fragments of pma AVL (Fig. 54). There are three examples of the distal segments (Figs 52J; 53C, D). Both seg- FIG. 48. — Bothriolepis ornata Eichwald, 1840, PMD in visceral view; A, LDM 100/354; B, LDM 100/408. Skujaine River near Klūnas vil- ments bear prominent lateral and mesial lage, Latvia. Tērvete Formation. Abbreviations: AMD, anterior me- spines. The spines are large and closely setting dian dorsal plate; MxL, mixilateral plate; PMD, posterior median dorsal plate; cf.AMD, area overlapping AMD; cf.MxL, area over- on the proximal segment, in large individuals lapping MxL; cr.tp, crista transversalis interna posterior; dmr, dorsal they are fusing at the base. The ventro-mesial median ridge of trunk armour; grm, ventral median groove; l, lateral corner of PMD; oa.MxL, area overlapped by MxL; pa, posterior margin is smoothed and rounded. The pectoral corner; plc, postero-lateral corner; pma, posterior marginal area; pit-line groove (sgp) is traced almost along the prv2, posterior ventral process of dorsal wall of trunk armour; ventro-mesial margin and can be seen not on pt2, posterior ventral pit; tb, ventral tuberosity. Scale bar: 10 mm. the MM2 as in B. canadensis, but on the CV1 and CV2 similar to B. cristata Traquair, 1895 mesial margin bears few rounded tubercles. and B. ciecere. The lateral spines of the distal The CD1 is moderately broad with L/B index segment are sharp and proximally directed, the about 2.7. The CV1 is slightly more elongate

GEODIVERSITAS • 2001 • 23 (4) 563 Lukševičs E.

A BF

A, B, D, E

F-H

FIG. 49. — Bothriolepis ornata Eichwald, 1840; A, B, PMD LDM 100/408 in dorsal and visceral views; C, ADL LDM 100/16; D, ADL LDM 100/412; E, ADL LDM 100/411; F, MxL LDM 100/21; G, PVL LDM 100/416; H, PVL LDM 100/27. Skujaine River near Klūnas village, Latvia. Tērvete Formation. Abbreviations: ADL, anterior dorso-lateral plate; MxL, mixilateral plate; PMD, posterior median dorsal plate; PVL, posterior ventro-lateral plate. Scale bars: 10 mm.

564 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

pnoa n.prpl BCoa.AMD dlm

f.art dlm

cri

oa.AVL pro IIm d oa.AVL dlg2 A dlr lcg D oa.PMD oa.AMD

cu F lcg dlr oa.PVL D, F

A-C, E

FIG. 50. — Bothriolepis ornata Eichwald, 1840; A-C, ADL; A, LDM 100/364 in dorsal view; B, LDM 100/16 in dorsal view; C, LDM 100/411 in anterior view; D-F, MxL; D, LGI 5/2058; E, LDM 100/21; F, LDM 100/20. Skujaine River near Klūnas village, Latvia. Tērvete Formation. Abbreviations: ADL, anterior dorso-lateral plate; AMD, anterior median dorsal plate; AVL, anterior ventro-lateral plate; MxL, mixilateral plate; PMD, posterior median dorsal plate; PVL, posterior ventro lateral plate; cri, infra-articular crista; cu, postero-ventral ornamented corner; d, dorsal corner of MxL; dlg2, posterior oblique dorsal sensory line groove; dlm, dorsal lamina of ADL; dlr, dorso-lateral ridge; f.art, articular fossa; lcg, main lateral line groove; llm, lateral lamina of ADL; n.prpl, notch in dorsal margin of ADL for external postlevator process of AMD; oa.AMD, area overlapped by AMD; oa.AVL, area overlapped by AVL; oa.PMD, area overlapped by PMD; oa.PVL, area overlapped by PVL; pnoa, postnuchal ornamented corner; pro, processus obstans. Scale bars: 10 mm.

GEODIVERSITAS • 2001 • 23 (4) 565 Lukševičs E.

c.al

ABcit1

prc cit2

oa.AVL

pbr pbr

f.ax

cf.MV D

vlr cf.PVL

A-C

C f.ax a.un

prc pe pbr fp vlr m.lim f.mp

FIG. 51. — Bothriolepis ornata Eichwald, 1840; A-C, AVL LDM 100/414; A, visceral view; B, ventral view; C, lateral view; D, disarticulated processus brachialis of the AVL LDM 100/365. Skujaine River near Klūnas village, Latvia. Tērvete Formation. Abbreviations: AVL, anterior ventro-lateral plate; MV, median ventral plate; MxL, mixilateral plate; PVL, posterior ventro lateral plate; a.un, unornamented area beneath fossa articularis pectoralis; c.al, antero-lateral corner of subcephalic division; cf.MV, area overlapping MV; cf.MxL, area overlapping MxL; cf.PVL, area overlapping PVL; cit1, crista transversalis interna anterior; cit2, transverse thickening; f.ax, axillary foramen; f.mp, protractor area; fp, funnel pit; m.lim, margo limitans of AVL; oa.AVL, area overlapped by AVL; p.br, processus brachialis; pe, pars pedalis; prc, prepectoral corner; vlr, ventro-lateral ridge. Scale bars: 10 mm.

566 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

A F BG

C I

A, D, E, H

DEJ

C, F, G, I, J

FIG. 52. — Bothriolepis ornata Eichwald, 1840; A, MxL LDM 100/20; B, MV LDM 100/30; C, disarticulated processus brachialis of the AVL LDM 100/365; D, E, AVL LDM 100/414 in visceral and ventral views; F, CD2 LDM 100/424; G, CD1 LDM 100/418; H, CD1 LDM 100/417; I, CV1 LDM 100/421; J, distal segment of pectoral fin LDM 100/45. Skujaine River near Klūnas village, Latvia. Tērvete Formation. Abbreviations: AVL, anterior ventro-lateral plate; CD1, 2, dorsal central plates 1 and 2; CV1, ventral central plate 1; MV, median ventral plate; MxL, mixilateral plate. Scale bars: 10 mm. than the CD1 (L/B 3.1). The CD2 is slightly The ornamentation is typically reticulate, in longer than broad. The CV2 is 4.5-5.1 times as quite large individuals becoming coarser and long as it is broad. The distal segment is sparser. The network of anastomosing ridges in normally developed, showing the CD3 and large individuals is broken into irregular ridges, CD4, but CD5, which is well-defined in but never into short ridges or tubercles. The B. leptocheira, in B. ornata is not present. irregular ridges are situated without any order,

GEODIVERSITAS • 2001 • 23 (4) 567 Lukševičs E.

AB C D

MM3 CV3 CD3 sgp

MM4 G

CD4

F ML4 E MM5

H CV4

FIG. 53. — Bothriolepis ornata Eichwald, 1840; A, B, CV1 LDM 100/422 in dorsal and ventral views; C, D, distal segment of the pectoral fin LDM 100/45 in ventral and dorsal views; E, CD1 LDM 100/418 in dorsal view; F, CD1 LDM 100/419 in dorsal view; G, CV1 LDM 100/421 in dorsal view; H, CD2 LDM 100/424 in dorsal view. Skujaine River near Klūnas village, Latvia. Tērvete Formation. Abbreviations: CD1-4, dorsal central plates 1 to 4; CV1, 3, 4, ventral central plates 1, 3 and 4; ML4, lateral marginal plate 4; MM3-5, mesial marginal plates 3, 4 and 5; sgp, pectoral pit-line groove. Scale bar: 10 mm. only one specimen of PMD shows ridges per- (collected by H. Helmersen, A. Olivieri & pendicular to margins of the plate. The orna- R. Hecker) were studied in details and com- mentation of the pectoral appendage remains pared with the material from Skujaine River, reticulate even in quite lagre individuals. The Latvia, collected by the author (hold in LDM) distal segment ornament consists of low longi- and Karatajūte-Talimaa (kept in LGI and PIN), tudinal ridges, which are weakly defined on the and attributed to the same species by Lukševičs ventral surface and more distinct on the dorsal (1992). The following account is the first full surface of the segment. treatment in English, all materials from the type locality and Latvia are described here. REMARKS Bothriolepis ornata was introduced by Eichwald DISCUSSION (1840) for specimen of the AMD collected by Bothriolepis ornata at the Skujaine locality is Helmersen at Priksha River (as indicated on the associated with B. jani (Lukševičs 1986). label), tributary of Msta River, near Borovichi B. ornata can be distinguished readily from town in the Novgorod region. The lectotype B. jani by its 1) larger size; 2) typical reticulate and four other specimen from the type locality ornament, which is tubercular in B. jani;

568 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

AB between them are insignificant and consist in that in B. ornata 1) the head-shield is slightly narrower and more arched; 2) the La and Pn are narrower; 3) the rostral margin of the La is shorter; 4) the mesial division of the Pn is of different shape. CD1 These could be intraspecific variations or preser- MM1 CV1 vation differences, but direct comparison of the Baltic and Greenland material is needed to solve sgp this problem.

Bothriolepis jani Lukševičs, 1986 (Figs 55-61) ML2 Bothriolepis jani Lukševičs, 1986: 131, pl. 1, fig. 8. ML2 HOLOTYPE. — Right MxL LDM 100/88.

MM2 MATERIAL EXAMINED. — LDM 100/526, articulated MM2 head-shield, LDM 100/66-108, 100/119-122, 100/137, 100/148, 100/374-377, 100/431-434, disarticulated plates of the trunk armour; 100/109-118, 100/123- 136, 100/370, 100/371, 100/378, 100/435-440, plates CV2 of the pectoral appendage; 100/144, 100/427, 2 Prm; 100/369, 100/428, 2 La; 100/429, LGI 5/2028, 2 Pp; CD2 LDM 100/138-143, 100/372, 100/430, 8 Nu.

LOCALITIES AND HORIZON. — The type locality is an exposure of white and pink sandstone containing FIG. 54. — Bothriolepis ornata Eichwald, 1840, proximal seg- abundant fish bones, dolomite marl and marl at the ment of the pectoral appendage LGI 5/2050A; A, dorsal view; right bank of Skujaine River down Klūnas village B, ventral view. Skujaine River near Klūnas village, Latvia. ē Tērvete Formation. Abbreviations: CD1, 2, dorsal central plates (number 8 in Fig. 1); the Famennian T rvete 1 and 2; CV1, 2, ventral central plates 1 and 2; ML2, lateral mar- Formation. Other material comes from an outcrop of ginal plate 2; MM1, mesial marginal plate 1; MM2, mesial mar- red and pink sandstone at the right bank of Svēte ginal plate 2; sgp, pectoral pit-line groove. Scale bar: 10 mm. River near Ķurbes hamlet (number 9 in Fig. 1); the Mūri Formation.

DIAGNOSIS. — Small Bothriolepis with a median dorsal armour length reaching about 65 mm. B/L index 3) shape and proportions of almost all trunk- of trunk-armour about 90. Prm broad, posterior mar- armour plates. B. ornata also resembles B. ciecere gin is slightly shorter than almost straight anterior by some features (see description of B. ciecere margin. Nu strongly arched, L/B index of 59; AMD for comparisons). strongly arched, B/L index 97. Anterior margin of AMD is broad, posterior margin of AMD and anteri- Bothriolepis hayi is a species that most resembles or margin of PMD are narrow. Median dorsal ridge B. ornata among Scottish Bothriolepis. B. ornata strongly developed. Lateral line sensory groove ter- differs from B. hayi most strikingly in the larger minates on posterior margin of the MxL. Proximal size and the narrower AMD and PMD, but also segment of pectoral appendage three times as long as broad, with prominent lateral and mesial spines. in the proportions of the Prm, La, Nu, Pn and Ornamentation reticulate in small individuals and more broad postnuchal ornamented corner of typically tuberculate in well-grown individuals, the ADL. consisting of numerous closely irregularly set round- B. ornata is morphologically close to B. groen- ed tubercles. landica (Stensiö 1948). The two species are of similar size, and have similar proportions and DESCRIPTION shape of almost all the head-shield, trunk-armour This species is represented mainly by disarticu- and pectoral appendage plates. The distinctions lated plates, single articulated, but slightly

GEODIVERSITAS • 2001 • 23 (4) 569 Lukševičs E.

A BFG

C H I E

DL K J

M N

OPR

FIG. 55. — Bothriolepis jani Lukševičs, 1986; A, head-shield 100/526 in dorsal view; B, Prm LDM 100/144; C, Pp LDM 100/429; D, La LDM 100/369; E, Nu LDM 100/141; F, paratype, Nu LDM 100/142; G, Nu LDM 100/430; H, PMD LDM 100/83; I, PMD LDM 100/76 in visceral view; J, K, paratype, AMD LDM 100/67 in dorsal and visceral views; L, AMD LDM 100/431; M, ADL LDM 100/121; N, ADL LDM 100/122; O, MxL LDM 100/432; P, MxL 100/377; R, holotype, MxL LDM 100/88. Skujaine River near Klūnas village, Latvia. Tērvete Formation. Abbreviations: La, lateral plate; Nu, nuchal plate; Pp, postpineal plate; Prm, premedian plate; ADL, anterior dorso-lateral plate; AMD, anterior median dorsal plate; MxL, mixilateral plate; PMD, posterior median dorsal plate. Scale bar: 10 mm. deformed head-shield and a single articulated index of about 127, and is strongly vaulted both proximal segment of the pectoral fin. The head- rostrocaudally and transversely. The rostral shield (Figs 55A; 56A) has an estimated B/L margin is convex, shorter than the posterior

570 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

margin, which is straight and bears a well- AB defined posterior median process. The antero- lateral corners and shallow prelateral notch are ifc1 Prm well-defined. The obtected nuchal area is long, La extending onto the Pn, it is broadest on the Nu. ifc2 ifc1 The orbital fenestra is relatively large (B/L index fe.orb about 176). The preorbital recess is of pentago- csl nal type. mr The Prm is broad, B/L index of about 116, C g arched, with an almost straight rostral margin, as in LDM 100/144, which is an anterior divi- Pn sion of the Prm (Fig. 55B). LDM 100/427 is a Nu d.end nm more complete smaller Prm (Fig. 56B) which is more arched, and broadest at the rostral margin. D E The rostral margin more than twice longer than the concave orbital margin. The infraorbital sensory groove crosses the plate far from the rostral margin, unlikely that in B. ornata. The mp anterior section of the supraorbital sensory line is not recognized. FGcsl cr.pto sot The La (Fig. 55D) is broad with L/B index of npp mc npp about 136-137 (n = 2). The rostral margin is of moderate breadth and almost straight. The infraorbital sensory groove crosses the plate almost in its middle part far from the orbital and lateral margins. The central sensory line groove pc nm d.end ood cr.tv (csl) extends slightly past the middle of the mppr socc cr.o orbital fenestra. The antero-lateral corner of the otico-occipital depression on the visceral surface FIG. 56. — Bothriolepis jani Lukševičs, 1986; A, head-shield LDM 100/526; B, Prm LDM 100/427; C, Pp LDM 100/429 in vis- is relatively narrow and extends forward at the ceral view; D-G, Nu; D, LDM 100/430 in dorsal view; E, LDM level of the middle of orbital fenestra length. 100/142 in dorsal view; F, G, LDM 100/372 in dorsal and visceral views. Skujaine River near Klūnas village, Latvia. Tērvete The preorbital recess is not clearly seen, but the Formation. Abbreviations: La, lateral plate; Nu, nuchal plate; outlines on the visceral surface of specimen Pn, paranuchal plate; Pp, postpineal plate; Prm, premedian plate; cr.o, median occipital crista; cr.pto, postorbital crista; LDM 100/369 allows to suggest that it could be cr.tv, transverse nuchal crista; csl, central sensory line groove; of trifid type. d.end, opening of canal for endolymphatic duct; fe.orb, orbital fenestra; g, paired pits on Pp; ifc1, principal section of infraor- The very broad Pp (LDM 100/429: Figs 55; 56C, bital sensory line on head-shield; ifc2, branch of infraorbital sen- and LGI 5/2028) has a strongly convex anterior sory line diverging on La; mc, lateral corner; mp, middle pit-line groove; mppr, posterior process on Nu; mr, median ridge of Pp; margin. A narrow median ridge (mr) separates nm, obtected nuchal area; npp, postpineal notch; ood, otico- the deep paired pits (g) on the visceral surface of occipital depression; pc, postero-lateral corner; socc, supraoccipital cross-commissural pit-line groove; sot, supraotic the plate. Both specimen clearly differ from the thickening. Scale bar: 5 mm. Pp of similar size (LDM 100/373) of B. ornata which comes from the same locality, by their tubercular ornament and broader general pro- (L/B index 57-63, 59 on the average). The ante- portions. rior division of the lateral margin is much short- The Nu (Figs 55E-G; 56D-G) is strongly arched er than the posterior division. The obtected with an angle between right and left halves nuchal area (nm) is relatively long, it extends on about 103-125°. It is relatively short and broad the Pn. In specimens LDM 100/140 and 100/372

GEODIVERSITAS • 2001 • 23 (4) 571 Lukševičs E.

cr.pl f.retr A B alr

cf.ADL dma pt1

dlg2 mvr lc

dmr

oa.MxL cf.MxL

grm oa.PMD

FIG. 57. — Bothriolepis jani Lukševičs, 1986, AMD; A, B, LDM 100/67 in dorsal and visceral views; C, LDM 100/119 in dorsal view; D, LDM 100/431 in dorsal view. Skujaine River near Klūnas village, Latvia. Tērvete Formation. Abbreviations: ADL, anterior dorso-lateral plate; AMD, anterior median dorsal plate; MxL, mixilateral plate; PMD, posterior median dorsal plate; alr, postlevator thickenings; cf.ADL, area overlapping ADL; cf.MxL, area overlapping MxL; cr.pl, postlevator crista; dlg2, posterior oblique dorsal sensory line groove; dma, tergal angle; dmr, dorsal median ridge; f.retr, levator fossa; grm, ventral median groove; lc, lateral corner; mvr, median ventral ridge; oa.MxL, area overlapped by MxL; oa.PMD, area overlapped by PMD; pt1, anterior ventral pit. Scale bar: 5 mm.

(Fig. 56F), there are supraoccipital grooves defined middle pit-line grooves (mp), which are (socc) which terminate little in front of the not connected with endolymphatic opening and obtected nuchal area at the large external open- extend to the lateral margin of the plate. The ings for the endolymphatic ducts (d.end). median occipital crista (cr.o) and the transverse Specimens LDM 100/141, 100/142, 100/430 nuchal crista are well-defined. The postorbital (Figs 55E-G; 56D-E), and 100/527 show well- crista (cr.pto) on the visceral surface is weakly

572 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

cf.AMD ABD

tb pt2 dmr

cf.MxL plc pa pma C cr.tp oa.AMD pnoa EF

dlm

pro dlr lcg

FIG. 58. — Bothriolepis jani Lukševičs, 1986; A-D, PMD; A, B, LDM 100/83 in dorsal and visceral views; C, LDM 100/84 in visceral view; D, LDM 100/80 in dorsal view; E, F, ADL; E, LDM 100/121; F, LDM 100/122. Skujaine River near Klūnas village, Latvia. Tērvete Formation. Abbreviations: ADL, anterior dorso-lateral plate; AMD, anterior median dorsal plate; MxL, mixilateral plate; PMD, posterior median dorsal plate; cf.AMD, area overlapping AMD; cf.MxL, area overlapping MxL; cr.tp, crista transversalis interna posterior; dlm, dorsal lamina; dlr, dorso-lateral ridge; dmr, dorsal median ridge; l, lateral corner of PMD; lcg, main lateral line groove; oa.AMD, area overlapped by AMD; pa, posterior corner; plc, postero-lateral corner; pma, posterior marginal area; pnoa, postnuchal ornamented corner; pro, processus obstans; pt2, posterior ventral pit; tb, ventral tuberosity. Scale bar: 5 mm. developed, it can be recognised only in LDM viduals it is broader than long, as in B. maxima. 100/372 (Fig. 56G) as a sharp transversely The plate is strongly arched, with right and left directed crest binding the orbital facets posteri- laminae forming an angle at the level of lateral orly. corners of about 115° on the average. The ante- The dorsal trunk armour is relatively broad, rior margin may be weakly concave or fairly B/L index 90. It is relatively low, with a later- straight. It is broad and 1.2-2 times as long as a al wall less than three times as long as high, narrow posterior margin. The tergal angle (dma) with high dorsal wall. Length of the dorsal is well-marked. The median dorsal ridge is wall reaches 65 mm. Right and left dorsal lam- strongly developed and in small individuals rep- inae enclose an angle about 115°. The dorsal resented by the low crest. Overlap areas for and lateral walls enclose an angle 120° in the MxL are developed as in Remigolepis (Stensiö MxL and about 125-130° in the ADL. The 1931). The visceral surface of the AMD shows a median dorsal ridge is well-defined. The broad levator fossa (f.retr), which is limited by dorso-lateral and ventro-lateral ridges are well- the low postlevator thickenings (alr) and strong- marked in a posterior part of the trunk ly developed postlevator crest (cr.pl) with pro- armour. nounced kink. The anterior edge of the crest do The AMD (Figs 55J-L; 57) with B/L index not reach a distinct, but narrow supranuchal about 91-110, 97 on the average, in large indi- area.

GEODIVERSITAS • 2001 • 23 (4) 573 Lukševičs E.

ABdlg2 oa.PMD oa.AMD C

lcg oa.PVL cu dlr lcg F E cit1

cit2 prc

cf.AVL p.br f.ax f.mp

f.ax D a.un

vlr cf.PVL

lcg

FIG. 59. — Bothriolepis jani Lukševičs, 1986; A-D, MxL in dorsal view; A, LDM 100/87; B, LDM 100/90; C, LDM 100/432; D, holotype LDM 100/88; E, F, AVL; E, LDM 100/433 in ventral view; F, LDM 100/102 in visceral view. Skujaine River near Klūnas village, Latvia. Tērvete Formation. Abbreviations: AMD, anterior median dorsal plate; AVL, anterior ventro-lateral plate; MxL, mixilateral plate; PVL, posterior ventro lateral plate; a.un, unornamented area beneath fossa articularis pectoralis; cf.AVL, area overlapping AVL; cf.PVL, area overlapping PVL; cit1, crista transversalis interna anterior; cit2, transverse thickening; cu, postero-ventral ornamented corner; dlg2, posterior oblique dorsal sensory line groove; dlr, dorso-lateral ridge; f.ax, axillary foramen; f.mp, protractor area of processus brachialis; La, lateral plate; lcg, main lateral line groove; oa.AMD, area overlapped by AMD; oa.PMD, area overlapped by PMD; oa.PVL, area overlapped by PVL; p.br, processus brachialis; prc, prepectoral corner; vlr, ventro-lateral ridge. Scale bar: 5 mm.

The PMD (Figs 55H-I; 58A-D) is arched, mod- exceeds height of the lateral lamina. Dorsal erately broad, B/L index about 87-104. The and lateral laminae of the plate enclosing an width of the anterior margin comprises about angle of 125-130°. The dorso-lateral ridge 54% of total breadth. The median dorsal ridge is (dlr) is well-defined in the posterior part of well-developed. the plate, it is rounded in the anterior third The ADL (Figs 55M, N; 58E, F) is moder- of the ADL. ately broad. The dorsal lamina is relatively The dorsal lamina of the MxL (Figs 55O-R; narrow and long, and its breadth a little 59A-D) is less than twice as long as it is broad.

574 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

A B FG

C A, B H-I

C-G HJI DE

FIG. 60. — A-G, Bothriolepis jani Lukševičs, 1986; A, B, AVL LDM 100/98 in ventral and visceral views; C, PVL LDM 100/434; D, CD1 plate LDM 100/144; E, CD1 LDM 100/436; F, ML2 LDM 100/378; G, proximal segment of the pectoral fin LDM 100/435. Skujaine River near Klūnas village, Latvia. Tērvete Formation; H-J, Bothriolepis heckeri n. sp.; H, holotype, AMD plate PIN 835/42 in dorsal view; I, incomplete AMD plate PIN 835/41 in dorsal view; J, incomplete La, Pn and Pmg PIN 835/40 in dorsal view. Malyi Tuder River not far from Bilovo village, Russia. Bilovo Beds(?). Abbreviations: AMD, anterior median dorsal plate; AVL, anterior ventro-lateral plate; CD1, central dorsal plate 1; ML2, lateral marginal plate 2; PVL, posterior ventro lateral plate; La, lateral plate; Pn, paranuchal plate; Pmg, postmarginal plate. Scale bars: 5 mm.

The dorsal lamina is 1.7 time as broad as the lat- The AVL (Figs 59E, F; 60A, B) is of moderate eral lamina is high. Dorsal and lateral laminae breadth, the ventral lamina is about 2.5 times as enclosing an angle about 120°. The lateral lami- long as it is broad. The ventral lamina 2.3 times na is relatively high, 2.4 times as long as it is as broad as the lateral lamina high in LDM broad. The dorso-lateral ridge is well-defined. 100/433 (Fig. 59E). Ventro-lateral ridge is well- The lateral line sensory groove terminates on defined. The axillary foramen (f.ax) is rather the posterior margin of the plate above the pos- large and slightly elongated in shape. The visceral tero-ventral ornamented corner (cu), posterior surface of the AVL shows the high transverse part of the sensory groove is traced not along anterior crista (cit1) running mesially subparallel the suture between the MxL and PMD as usual- to the low and broad transverse thickening ly in Bothriolepis, but on the outer surface of the (cit2), just like as in B. ciecere, B. macphersoni MxL. Young, 1888 and B. karawaka Young, 1888.

GEODIVERSITAS • 2001 • 23 (4) 575 Lukševičs E.

oa.AVL ACbroad, it occupies only 17.7% of the total PVL length. The lateral lamina is 2.6 times as long as it is high, the ventral lamina is 1.5 time as broad as the lateral lamina high. The ventral and lateral laminae encloses the angle about vlr 112°. The ventro-lateral ridge (vlr) is well- developed. The MV is unknown, but the shape of the AVL dc and PVL suggests the small size of the MV. The pectoral fin is represented mostly by disarticulated bones, and specimen LDM 100/435 (Figs 60G; 61B) showing articulated plates of the proximal segment without the most proxi- B mal part. The proximal segment bears large prominent lateral and mesial spines. It is rela- DF tively broad, about three times as long as it is CD1 broad. The CD1 is of moderate size with L/B index varying from 2.8 to 3. The CV1 is slightly more elongated than the CD1 (L/B 3.3). The ML2 is 4.4-5.5 (4.9 on the average) as long as it is broad. The ornamentation is reticulate in small individuals and typically tuberculate in well-grown ML2 individuals. It consists of numerous closely and E MM2 usually irregularly set tubercles, which usually are rounded. They are tall on the Prm and short on most of the other plates. Along the obtected nuchal area on the Nu and posterior margin of the lateral lamina of the PVL tubercles may fuse into ridges. More regular setting of tubercles is recognized on the proximal segment of the CD2 pectoral fin.

REMARKS The holotype and most of the material (collec- FIG. 61. — Bothriolepis jani Lukševičs, 1986; A, PVL LDM 100/434; B, proximal segment of the pectoral appendage LDM tion LDM 100) came from the Skujaine 100/435; C, CD1 LDM 100/130; D, CD1 LDM 100/133; E, CV1 locality, collected by the author in 1984, 1989 LDM 100/134; F, ML2 LDM 100/378. Skujaine River near Klūnas village, Latvia. Tērvete Formation. Abbreviations: CD1, 2, central and 1998. Some studied specimens (e.g., LGI dorsal plates 1 and 2; CV1, ventral central plate 1; ML2, lateral 5/2028) were found by Karatajūte-Talimaa in marginal plate 2; MM2, mesial marginal plate 2; dc, dorsal corner of lateral lamina; oa.AVL, area overlapped by AVL; the same locality. Other material (e.g., LDM PVL, posterior ventro lateral plate; vlr, ventro-lateral ridge. Scale 100/524) was collected by the author in the bar: 5 mm. Ķurbes locality.

There are two complete PVL LDM 100/434 DISCUSSION (Figs 60C; 61A) and LDM 100/375. In LDM B. jani differs from most of other Bothriolepis 100/434, its ventral lamina is 2.1 times as long by its tuberculate ornament, which is similar to as it is broad. The subanal division is relatively that of Grossilepis tuberculata and G. spinosa.

576 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

B. jani differs from G. tuberculata in its 1) shape A and proportions of the PMD, MxL and PVL; ifc2 2) sutural connections of the AMD and MxL; 3) shape of the postnuchal ornamented corner of lpr the ADL; 4) larger axillary foramen; 5) propor- La tions of pectoral fin bones. ifc1 cir Most of the described specimens come from the orb locality at Skujaine River downstream Klūnas Pmg village, associated with B. ornata. A comparison of B. jani with B. ornata is given at the end of Pn the description of B. ornata. B. jani can be distinguished readily from the other Famennian Bothriolepis species of similar size (B. cristata, B. hydrophila [Miles 1968] and small specimens of B. ciecere) by its tuberculate dma ornament. B. jani differs well from B. nielseni B E dlg2 Stensiö, 1948 in absence of the crest on the dorso-lateral ridge. Bothriolepis, described by Gross (1942) from locality at Svēte River, resembles B. jani by its tubercular ornament but differs in absence of a prominent ventro-lateral ridge on the PVL. The species B. jani and B. lohesti Leriche, 1931 (see Stensiö 1948) from Belgium are similar in 1) the shape and proportions of the AMD; 2) sutural connections crd between AMD and MxL. Unfortunately, oa.PMD C dma B. lohesti is only represented by a few remains crd crd of AMD, ADL and pieces of the pectoral fin D bones. It differs in that 1) the AMD is less arched; 2) ornament consists of tubercles and nodose ridges, but it seems likely that B. jani and B. lohesti may be phylogenetically very oa.PMD dlg2 close. FIG. 62. — Bothriolepis heckeri n. sp.; A, incomplete La, Pn and Pmg PIN 835/40; B-D, holotype, AMD PIN 835/42; B, dorsal view; C, lateral view; D, anterior view; E, incomplete Bothriolepis heckeri n. sp. AMD PIN 835/41 in dorsal view. Malyi Tuder River not far from Bilovo village, Novgorod region, Russia. Bilovo Beds(?). (Figs 60H-J; 62) Abbreviations: AMD, anterior median dorsal plate; PMD, posterior median dorsal plate; La, lateral plate; Pmg, postmargin- HOLOTYPE. — AMD PIN 835/42. al plate; Pn, paranuchal plate; cir, semicircular pit-line groove; crd, dorsal median crista; dlg2, posterior oblique dorsal sen- MATERIAL EXAMINED. — PIN 835/41, an incomplete sory line groove; dma, tergal angle; ifc1, principal section of AMD; PIN 835/40, an incomplete La, Pn and Pmg; infraorbital sensory line; ifc2, branch of infraorbital sensory line diverging on La; lpr, lateral process; oa.PMD, area over- all gathered by R. Hecker in 1930. lapped by PMD; orb, orbital margin. Scale bar: 10 mm. LOCALITY AND HORIZON. — Outcrop at the right bank of Malyi Tuder River not far from Bilovo village, Novgorod region, Russia; Bilovo Beds(?), Famennian. (B/L index of about 81) which bears high dorsal median crest arising just anteriorly the tergal angle. La DIAGNOSIS. — Moderately large Bothriolepis with is broad with very long infraorbital sensory groove comparatively narrow and strongly arched AMD diverging on La.

GEODIVERSITAS • 2001 • 23 (4) 577 Lukševičs E.

DESCRIPTION Bothriolepis ciecere Lyarskaja PIN 835/42 is a relatively small almost complete in Lyarskaja & Savvaitova, 1974 AMD with damaged antero-lateral corners (Figs 63-76) (Figs 60H; 62B-D) and PIN 835/41 is an imper- Bothriolepis ciecere Lyarskaja in Lyarskaja & fect AMD without the right lateral margin and Savvaitova, 1974: 99-104, pl. I, fig. 1. loosed left postero-lateral margin (Figs 60I; Bothriolepis ornata Eichw. – Gross 1933: 41. 62E). The AMD is comparatively narrow with B/L index of about 81, with a gently concave Bothriolepis cf. ornata Eichw. – Gross 1942: 421-422, anterior margin, which is moderately broad. abb. 2. — Lyarskaja & Savvaitova 1974: 97. The posterior margin is relatively narrow, about Bothriolepis pavariensis – Lyarskaja & Savvaitova 1.2 time shorter than the anterior margin. The 1974: 104, pl. I, figs 5-7; text-figs 9-10. AMD is strongly arched with the angle between HOLOTYPE. — AMD LDM 43/303. the two laminae about 100°, and bears a 2-3 mm MATERIAL EXAMINED. — LDM 43/301, 43/303-306, high dorsal median crest (cr.d) which arises just 43/337, 43/5082, 43/5095, 43/5120, 57/1-97, 57/398, anteriorly the tergal angle. The antero-lateral 57/721, 57/722, 57/724-726, 57/728-733, 57/896, corner is weakly defined. The tergal angle is 57/906, 57A/1, 81/1-41, 81/43-46, 81/48-94, 81/96-98, situated slightly posteriorly the anterior third of 81/126, 81/127, 81/136-155, 81/157-164, 81/170-183, 81/190-275, 81/279-351, 81/356-358, 81/360-363, the plate. The posterior oblique dorsal sensory 81/365-377, 81/380-393, 81/406-504, 81/533-549, line grooves (dlg2) are well-defined. The orna- 81/554-556, 81/558-577, LGI 5/2020 - 5/2044): artic- ment is reticular, sometimes with slightly ulated head-shields and their fragments, disarticulated plates of the head-shield, trunk-armour and pectoral defined ridges. appendage. PIN 835/40 is an incomplete head-shield consisting of the Pn, Pmg and incomplete La LOCALITIES AND HORIZON. — The type locality is an outcrop at the left bank of Ciecere River down- which lacks the margin making contact with stream from the Pavāri hamlet; upper Famennian, the Prm (Figs 60J; 62A). The La plate is rela- the middle Member of the Ketleri Formation. tively broad as it is preserved, with gently Other material comes from an outcrop exposing defined antero-lateral corner. The infraorbital light sand and sandstone at the right bank of Venta River 1 km W from Ketleri hamlet; the upper sensory groove crosses the plate far from the Member of the Ketleri Formation. A probable lateral and rostral margins. The central sensory other undescribed subspecies of B. ciecere comes line groove (csl) seem to finish at the level of from Rybnitsa quarry, Oryol region of Russia; the middle of an orbital fenestra length. The Turgenevo Beds of the Plavsk Regional Stage, Famennian (Lebedev 1995; Lebedev & Lukševičs branch of the infraorbital sensory groove 1996). diverging on La (ifc2) is well-defined and DIAGNOSIS. — Rather large Bothriolepis with a unusually long. The Pn seems to be relatively median dorsal armour length of at least 200 mm. broad as it is preserved. The Pmg of unusual Dorsal wall of moderate width, B/L index of shape with the median margins longer than the trunk-armour about 77. B/L index of the head- lateral margins. shield of 120. Preorbital recess of trifid type. Orbital edges of Prm and La thickened. Anterior margin of the head-shield is rounded. Orbital DISCUSSION fenestra is not large. Prm broad, posterior margin is Bothriolepis heckeri n. sp. differs from all the slightly shorter than anterior margin. Nu strongly other known Bothriolepis from the Main vaulted, moderately broad, L/B index of 80. AMD moderately broad, B/L index 87. Posterior margin Devonian Field in its broad La with unusually of AMD and anterior margin of PMD are very situated sensory grooves. B. cristata (Miles narrow. Median dorsal ridge poorly developed. 1968) from the Rosebrae Beds of Scotland also Dorsolateral ridge well-marked, bears smooth has a strongly developed dorsal median crest, tubercles. Ventrolateral ridge strongly developed forming a well-defined crest in a posterior part of but differs in other shape and general propor- armour. Ornamentation typically reticulate, in quite tions of the AMD. large individuals becoming coarser and sparser.

578 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

A BCE

G HI JT KL

R S O

V ZU

FIG. 63. — Bothriolepis ciecere Lyarskaja in Lyarskaja & Savvaitova, 1974; A-C, head-shields in dorsal (A) and visceral (B, C) views; A, B, LDM 81/545; C, LDM 81/407; E-J, Pi in dorsal (E, G, I) and visceral (F, H, J) views; E, F, LDM 57/10; G, H, LDM 57/13; I, J, LDM 57/12; K-N, Prl in dorsal (K-M) and visceral (N) views; K, LDM 57/732; L, LDM 57/910; M, N, LDM 57/7; O, P, Prm LDM 57/2 in dorsal and visceral views; R-Z, La in dorsal (R, T, Z) and visceral (S, U, V) views; R, S, LDM 81/602; T, U, LDM 57/5; V, Z, LDM 81/410. A-C, R, S, V, Z, Ciecere River near Pavāri hamlet, Latvia; E-P, T, U, Venta River near Ketleri hamlet, Latvia. Ketleri Formation. Abbreviations: La, lateral plate; Pi, pineal plate; Prl, prelateral plate; Prm, premedian plate. Scale bar: 10 mm.

DESCRIPTION which is weakly convex. There are well-defined The head-shield (Figs 63A-C; 65A, B) was not anterolateral corners (alc) and the deep prelater- described by Lyarskaja (Lyarskaja & Savvaitova al notch (nprl). The obtected nuchal area (nm) is 1974). It is strongly vaulted both rostrocaudally short, broadest on the Nu, with slightly defined and transversely. The rostral margin is strongly lateral and median processes. The orbital fenes- convex, much shorter than the posterior margin, tra is relatively small, with a B/L index about

GEODIVERSITAS • 2001 • 23 (4) 579 Lukševičs E.

ACEF

D B JK

T U

FIG. 64. — Bothriolepis ciecere Lyarskaja in Lyarskaja & Savvaitova, 1974; A-D, La in dorsal (A, C) and visceral (B, D) views; A, B, LDM 81/629; C, D, LDM 81/628; E-O, Nu in dorsal (E, G, H, J, L, N) and visceral (F, I, K, M, O) views; E, F, LDM 81/698; G, LDM 81/811; H, I, LDM 57/14; J, K, LDM 57/723; L, M, LDM 57/18; N, O, LDM 57/909; P, articulated Nu and Pp 81/412 in dorsal view; R, S, Sm LDM 57/328 in dorsal and visceral views; T, U, Pn 57/721 in dorsal and visceral views. A-G, P, Ciecere River near Pavāri hamlet, Latvia. H-O, R-U, Venta River near Ketleri hamlet, Latvia. Ketleri Formation. Abbreviations: La, lateral plate; Nu, nuchal plate; Pn, paranuchal plate; Pp, postpineal plate; Sm, submarginal plate. Scale bar: 10 mm.

190 (n = 6). The orbital edges of the Prm and The visceral skull surface (Fig. 63B, C) shows La are thickened, similarly as in B. ornata, the broad otico-occipital depression (ood), which B. macphersoni and B. karawaka. is well-defined by the paramarginal cristae

580 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

ifc1 soc ifc1 ifc2 A ifc2 BE Prm cir nprl La fe.orb csl cir Pp Nu Pn Pmg nm d.end D csl C HIifc2

F J cr.pm a.Prl GS nprl p

ood tlg K

a2Sm cr.tv ad2 L ad1 M prh N

pr.po OPcsl R ood

sot d.end cr.tv

nm d.end cr.o

FIG. 65. — Bothriolepis ciecere Lyarskaja in Lyarskaja & Savvaitova, 1974; A, B, head-shields in dorsal view; A, LDM 81/25; B, LDM 81/545; C, D, Prm; C, LGI 5/2034; D, LDM 57/2; E-G, La; E, F, LDM 57/5 in dorsal and visceral views; G, LGI 5/2044; H-J, left-side Prl; H, I, LDM 57/7 in dorsal and visceral views; J, LDM 57/732 in dorsal view; K, Pi LDM 57/10; L, M, Sm LDM 57/328 in dorsal and visceral views; N-R, Nu in dorsal (N, O, R) and visceral (P) views; N, LGI 5/2029; O, P, LDM 57/18; R, LGI 5/2025; S, Pn LDM 57/721 in visceral view. A, B, Ciecere River near Pavāri hamlet, Latvia. C-S, Venta River near Ketleri hamlet, Latvia. Ketleri Formation. Abbreviations: La, lateral plate; Nu, nuchal plate; Pmg, postmarginal plate; Pn, paranuchal plate; Pp, postpineal plate; Prl, prelateral plate ; Prm, premedian plate; Sm, submarginal plate; ad1, 2, anterior and posterior articular processes; a.Prl, attachment area for Prl; a2Sm, posterior attachment area for Sm; cir, semicircular pit-line groove; cr.o, median occipital crista; cr.pm, paramarginal crista; cr.tv, transverse nuchal crista; csl, central sensory line groove; d.end, opening of canal for endolymphatic duct; fe.orb, orbital fenestra; ifc1, principal section of infraorbital sensory line; ifc2, branch of infraorbital sensory line diverging on La; nm, obtected nuchal area; nprl, prelateral notch; ood, otico- occipital depression; p, lateral pit of head-shield; prh, preorbital recess; pr.po, antero-lateral corner of otico-occipital depression; soc, anterior section of the supraorbital sensory line; sot, supraotic thickening; tlg, transverse lateral groove. Scale bar: 10 mm.

(cr.pm). The antero-lateral corner of otico- laterally over the middle of the Pn’s posterior occipital depression (pr.po) is broad in its base, margin. The transverse lateral groove (tlg) is postero-lateral corner is rounded and extends moderately broad and clearly defined. A broad

GEODIVERSITAS • 2001 • 23 (4) 581 Lukševičs E.

A BD

C-E

A, B, F

C E

FIG. 66. — Bothriolepis ciecere Lyarskaja in Lyarskaja & Savvaitova, 1974, AMD in dorsal (A, C-F) and visceral (B) views; A, B, LDM 57/25; C, holotype LDM 43/303; D, LDM 81/725; E, LDM 81/533; F, LDM 81/372. C-F, Ciecere River near Pavāri hamlet, Latvia. A, B, Venta River near Ketleri hamlet, Latvia. Ketleri Formation. Abbreviation: AMD, anterior median dorsal plate. Scale bars: 10 mm. shallow depression anteriorly from the antero- tly defined nasal notch (pnn). The anterior sec- lateral corner of preorbital recess is the lateral tion of the supraorbital sensory line (soc) is pit (p), which is situated equally spaced from an observed not always. There are several tubercles orbital edge of La and prelateral notch. The and pits of various shape and size usually situat- lateral margin shows very broad attachment ed on the dorsal surface of the preorbital recess. areas for the Sm with the strikingly short poste- The La (Figs 63O, P; 64A-D; 65E-G) is moder- rior one (a.2Sm). The attachment area for the Prl ately broad with the L/B index 136 on the aver- is almost laterally rather then ventrally faced. age. The rostral margin is of moderate breadth The median occipital crista (cr.o) is slightly and almost straight, the antero-median and defined, often it consists of several radially antero-lateral corners are well-defined. situated small ridges. The Pi (Figs 63E-J; 65K) was for the first time The Prm (Figs 63O, P; 65C, D) with B/L index described by Lukševičs (1991), it is known only 94-118. A rostral angle (ac) is present in half of from the Ketleri locality. Pi is relatively broad, large individuals. The orbital margin bears gen- breadth slightly exceeds a length. There is a

582 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

A BC Ff.retr dlg2 cf.ADL

pt1

DEnpn sna pr.pl cf.ADL

alr dma pt1 cf.MxL dlg2 mvr grm lc

cf.MxL oa.MxL oa.PMD

FIG. 67. — Bothriolepis ciecere Lyarskaja in Lyarskaja & Savvaitova, 1974, AMD in dorsal (A-D) and visceral (E, F) views; A, LDM 81/251; B, LDM 81/36; C, LDM 81/28; D, E, LGI 5/2020; F, LDM 57/25. A-C, Ciecere River near Pavāri hamlet, Latvia. D-F, Venta River near Ketleri hamlet, Latvia. Ketleri Formation. Abbreviations: ADL, anterior dorso-lateral plate; MxL, mixilateral plate; PMD, posterior median dorsal plate; alr, postlevator thickening; cf.ADL, area overlapping ADL; cf.MxL, area overlapping MxL; dlg2, posterior oblique dorsal sensory line groove; dma, tergal angle; f.retr, levator fossa; grm, ventral median groove; lc, lateral corner; mvr, median ventral ridge; npn, postnuchal notch; oa.MxL, area overlapped by MxL; oa.PMD, area overlapped by PMD; pr.pl, external postlevator process; pt1, anterior ventral pit; sna, supranuchal area. Scale bar: 10 mm. broad area without ornamentation along the small individuals, in well-grown specimens posterior margin. A deep, but small pineal pit sometimes it is present only on one side of the and antero-laterally situated paired tubercles are plate (LGI 5/2025: Fig. 65R), interrupted or present on the visceral surface of the plate. very short (LDM 57/14: Fig. 64H; LDM 57/18: Position of the pineal pit is marked on the outer Fig. 64L; LDM 57/723: Fig. 64J). In some cases surface by the pineal elevation or pineal fenestra. there are short supraoccipital grooves, which The Nu (Figs 64E-O; 65N-R) is vaulted terminate little in front of the obtected nuchal (Lyarskaja & Savvaitova 1974) with an angle area at the rather large external openings for the between right and left halves slightly larger than endolymphatic ducts (d.end). Postorbital crista 130°, L/B index 68-93, 80 on the average. The on the visceral surface is low. anterior division of the lateral margin is concave The Pn is of moderate breadth, L/B index 88- even in very large specimen, but not straight, as 110. The lateral division of the Pn is relatively was shown by Lyarskaja for B. pavariensis narrow composing 40-50% of the general (Lyarskaja & Savvaitova 1974: fig. 9), and a little breadth of a plate. The Pmg is relatively broad shorter than the posterior division. The shape of with lateral margins slightly longer than the the posterior margin is variable, however it median margins (Lyarskaja & Savvaitova 1974). always bears the posterior process (mppr). The The single Sm (extralateral) (Figs 64R, S; 65L, M), central sensory line groove is clearly distinct in collected by Lukševičs (LDM 57/328) is relatively

GEODIVERSITAS • 2001 • 23 (4) 583 Lukševičs E.

A B

A, B, D-H

C E F

FIG. 68. — Bothriolepis ciecere Lyarskaja in Lyarskaja & Savvaitova, 1974, PMD; A, B, LDM 57/722 in dorsal and visceral views; C, LGI 5/2023, in dorsal view; D-H, ADL in dorsal view; D, LDM 81/708; E, LDM 43/306; F, LDM 81/709; G, LDM 81/371; H, LDM 81/556. D-H, Ciecere River near Pavāri hamlet, Latvia. A-C, Venta River near Ketleri hamlet, Latvia. Ketleri Formation. Abbreviations: ADL, anterior dorso-lateral plate; PMD, posterior median dorsal plate. Scale bars: 10 mm. short with a L/B index about 150. The dorsal ADL and MxL (LDM 81/58-81/60), and several margin has a prominent anterodorsal process articulated bones. Plasticine reconstruction was and posterior attachment area for the skull. The used to describe the features of the trunk- posterior margin is strongly convex, the ventral armour. margin is weakly concave. The trunk-armour was not described by The trunk-armour in individuals of moderate Lyarskaja (Lyarskaja & Savvaitova 1974) in size is known from many isolated plates, partial details. In individuals of moderate size it is rela- dorsal wall of the trunk-shield prepared from tively broad (B/L index 77), low, with a lateral visceral surface consisting of AMD, PMD, left wall less than three times as long as it is high; in

584 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

oa.MxL

plc E

dmr pa cf.AMD B D grm

cf.MxL

plc

cr.tp pt2 pma pa

FIG. 69. — Bothriolepis ciecere Lyarskaja in Lyarskaja & Savvaitova, 1974, PMD; A, B, LGI 5/2023 in dorsal and visceral views; C, D, LDM 57/722, in dorsal and visceral views; E, 81/704 in dorsal view. A-D, Venta River near Ketleri hamlet, Latvia. E, Ciecere River near Pavāri hamlet, Latvia. Ketleri Formation. Abbreviations: AMD, anterior median dorsal plate; MxL, mixilateral plate; PMD, posterior median dorsal plate; cf.AMD, area overlapping AMD; cf.MxL, area overlapping MxL; cr.tp, crista transversalis interna posterior; dmr, dorsal median ridge; grm, ventral median groove; l, lateral corner; oa.MxL, area overlapped by MxL; pa, posterior corner; plc, postero-lateral corner; pma, posterior marginal area; pt2, posterior ventral pit. Scale bar: 10 mm.

GEODIVERSITAS • 2001 • 23 (4) 585 Lukševičs E.

A ly concave or less often fairly straight (in large individuals), moderately broad and 1.1-1.7 time as long as a narrow posterior margin. Overlap areas for the ADL and MxL are normally developed as usually in Bothriolepis, but in pnoa LDM 43/5082 and 81/30 the AMD overlaps n.prpl the MxL by a short anterior part of the poste- oa.AMD rior division of the lateral margin and in LDM B 81/262 sutural connection of the AMD plate with the MxL is of Remigolepis type. The dlm anterior (dlg1) and posterior (dlg2) oblique dorsal sensory line grooves are well-defined only on the plates of individuals of small and pro dlr lcg moderate size. In many cases there are variations in the course of the dlg2 noticed, as in FIG. 70. — Bothriolepis ciecere Lyarskaja in Lyarskaja & B. canadensis (Graham-Smith 1978): the dlg2 is Savvaitova, 1974, ADL; A, LDM 81/62; B, LDM 81/245. Ciecere River near Pavāri hamlet, Latvia. Ketleri Formation. Abbreviations: short on the right (LDM 81/252) or left (LDM ADL, anterior dorso-lateral plate; AMD, anterior median dorsal 81/253) side, as well as on both sides, and ter- plate; dlm, dorsal lamina; dlr, dorso-lateral ridge; lcg, main lateral line groove; n.prpl, notch in dorsal margin of ADL for minate in front of the postero-lateral margin external postlevator process of AMD; oa.AMD, area overlapped (LDM 81/28, 81/29, 81/48, 81/250 A, LGI by AMD; pnoa, postnuchal ornamented corner; pro, processus obstans. Scale bar: 10 mm. 5/2021). Sometimes the groove swings round, becoming directed anterolaterally and terminates at the AMD/ADL suture (LDM 81/36, comparison with some other species rather flat- 81/372: Figs 67B; 66F). The dlg2 in 20% of tened with low dorsal wall. The length of the the moderate size individuals are not present. dorsal wall, probably, reaches more than The visceral surface of the AMD shows a slight- 200 mm. The ventral wall is not quite flat, but ly lengthened levator fossa (f.retr), which is lim- slightly vailted transversely. It is gently arched ited by the low postlevator thickenings (alr). also in rostrocaudal direction in the posterior The anterior ventral pit (pt1) and the median division of the armour. The median dorsal ridge ventral ridge (mvr) are low in individuals of is weakly defined, it is present only in the poste- small and moderate size, in some specimens the rior quarter of the PMD. The dorso-lateral and median ventral ridge is very weakly defined. In ventro-lateral ridges are well-marked, strongly quite large individuals and especially on the developed in a posterior part of the armour plates, occurring from Ketleri site, on the con- forming a well-defined crests. Both ridges bear a trary, the anterior ventral pit is deep and median row of numerous, closely set smooth tubercles, ventral ridge is rather high. The median ventral which gradually increase in caudal direction. groove (grm) is short and usually terminates This feature distinguishes B. ciecere from all the anteriorly to the posterior margin. The AMD other known Bothriolepis from the Baltics, from the Ketleri locality differ a little from resembling B. nielseni from Greenland (Stensiö specimens, found at Ciecere River, by greater 1948: text-fig. 308). thickness. The AMD (Figs 66; 67) is moderately broad, The PMD (Figs 68A-C; 69) is narrow with the B/L index about 76-98, 87 on the average. The B/L index about 80-91, 86 on the average. It is anterior part of the plate is arched, with right almost flat in the anterior part and arched in the and left laminae forming an angle at the level posterior part. The width of a narrow anterior of lateral corners of about 139°, posterior part margin varies between 37-44% of total breadth is more flattened. The anterior margin is weak- of the plate (Lyarskaja incorrectly mentioned

586 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

A BC

A-F, H, K E

D H

F K

G, I, J

FIG. 71. — Bothriolepis ciecere Lyarskaja in Lyarskaja & Savvaitova, 1974; A-G, MxL; A, LDM 81/424; B, LDM 81/423; C, LDM 81/193; D, LDM 81/429; E, 81/540; F, LDM 81/712; G, LDM 81/424; H, MV LDM 81/722; I, J, articulated ADL, AVL, CD1 and CV1 LDM 81/434, in ventral and lateral views; K, AVL LDM 81/630 in visceral view. Ciecere River near Pavāri hamlet, Latvia. Ketleri Formation. Abbreviations: ADL, anterior dorso-lateral plate; AVL, anterior ventro-lateral plate; CD1, central dorsal plate 1; CV1, ventral central plate 1; MV, median ventral plate; MxL, mixilateral plate. Scale bars: 10 mm.

GEODIVERSITAS • 2001 • 23 (4) 587 Lukševičs E.

A B

dlr lcg C D

cu oa.PVL d dlg2 F dlg2 oa.PMD E oa.ADL

lcg dlg2 dlg2’ dlr GH

FIG. 72. — Bothriolepis ciecere Lyarskaja in Lyarskaja & Savvaitova, 1974, MxL in dorsal (A-C, E-H) and lateral (D) views; A, LDM 81/191; B, LDM 81/232; C, D, LDM 81/196; E, LDM 81/190; F, LDM 81/7; G, LDM 81/210; H, LDM 81/211. Ciecere River near Pavāri hamlet, Latvia. Ketleri Formation. Abbreviations: ADL, anterior dorso-lateral plate; MxL, mixilateral plate; PMD, posterior median dorsal plate; PVL, posterior ventro lateral plate; cu, postero-ventral ornamented corner; d, dorsal corner; dlg2, posterior oblique dorsal sensory line groove; dlg2’, additional branch of posterior oblique dorsal sensory line groove; dlr, dorso-lateral ridge; lcg, main lateral line groove; oa.ADL, area overlapped by ADL; oa.PMD, area overlapped by PMD; oa.PVL, area overlapped by PVL. Scale bar: 10 mm.

that the anterior margin is 3-3.5 times shorter than lamina is relatively narrow and long, and its the posterior margin). Specimen LGI 5/2023 breadth a little exceeds height of the lateral lami- (Fig. 69A) shows the abnormally developed na (Lyarskaja & Savvaitova 1974). The dorsal overlap area for the MxL, probably arisen as a and lateral laminae of the plate enclosing an result of damage of a living animal bone. angle of 120-125°. Specimen LDM 81/421 The ADL (Figs 68D-H; 70) is slightly shorter shows the dorsal overlap area partly overlaping than the MxL in articulated armour. The dorsal the AMD.

588 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

A HC

D B L

EFG

I JK OP

FIG. 73. — Bothriolepis ciecere Lyarskaja in Lyarskaja & Savvaitova, 1974; A, articulated AVL and proximal segments of pectoral fin LDM 81/716 in ventral view; B, articulated AVL LDM 81/318 and 81/319 in ventral view; C, AVL LDM 81/631 in ventral view; D, AVL in visceral view with articulated proximal segment of pectoral fin, Nu and Pp in dorsal view, LDM 81/435; E, proximal segment of pectoral fin LDM 81/724 in dorsal view; F, G, proximal segment of pectoral fin LDM 81/723 in ventral and dorsal view; H, I, CV1 in ventral view; H, LDM 81/338; I, LDM 81/339; J-K, ML2 in dorsal view; J, LDM 81/634; K, LDM 81/334; L-P, CD1 in dorsal view; L, LDM 81/345; M, LDM 81/341; N, LDM 81/575; O, LDM 81/325; P, LDM 81/336. Ciecere River near Pavāri hamlet, Latvia. Ketleri Formation. Abbreviations: AVL, anterior ventro-lateral plate; CD1, central dorsal plate 1; CV1, ventral central plate 1; ML2, lateral marginal plate 2; Nu, nuchal plate; Pp, postpineal plate. Scale bar: 10 mm.

GEODIVERSITAS • 2001 • 23 (4) 589 Lukševičs E.

AB C

A-E c.al F cit1 oa.AVL EDcit2 cf.AVL prc

CD1 f.ax p.br

f.ax

ML2 cf.MV

MM2 cf.PVL vlr CD2 p.br cf.ADL f.ax a.un F, G G

fp vlr f.mp pe m.lim

FIG. 74. — Bothriolepis ciecere Lyarskaja in Lyarskaja & Savvaitova, 1974, AVL in ventral (A-D, F), visceral (E) and lateral (G) views; A, LDM 81/3; B, LDM 81/4; C, LDM 81/70; D, LDM 81/631; E, AVL with articulated proximal segment of pectoral fin LDM 81/435; F, G, LDM 81/718. Ciecere River near Pavāri hamlet, Latvia. Ketleri Formation. Abbreviations: ADL, anterior dorso-lateral plate; AVL, anterior ventro-lateral plate; MV, median ventral plate; PVL, posterior ventro lateral plate; a.un, unornamented area beneath fossa articularis pectoralis; c.al, antero-lateral corner of subcephalic division; CD1, dorsal central plate 1; CD2, dorsal central plate 2; cf.ADL, area overlapping ADL; cf.AVL, area overlapping AVL; cf.MV, area overlapping MV; cf.PVL, area overlapping PVL; cit1, crista transversalis interna anterior; cit2, transverse thickening; f.ax, axillary foramen; f.mp, protractor area of processus brachialis; fp, funnel pit of processus brachialis; ML2, lateral marginal plate 2; m.lim, margo limitans; MM2, mesial marginal plate 2; oa.AVL, area overlapped by AVL; p.br, processus brachialis; pe, pars pedalis of processus brachialis; prc, prepectoral corner; vlr, ventro-lateral ridge. Scale bars: 10 mm.

The MxL (Figs 71A-G; 72) is moderately long. Dorsal and lateral laminae enclosing an angle The dorsal lamina of the plate is less than about 111°, but not 135° as claimed Lyarskaja twice (1.8 on the average) as long as it is broad. (Lyarskaja & Savvaitova 1974). The lateral lamina

590 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

A BC

A, C, F F

D E

D, E

B, G, H

FIG. 75. — Bothriolepis ciecere Lyarskaja in Lyarskaja & Savvaitova, 1974; A-F, PVL in ventral view; A, LDM 81/567; B, LDM 81/445; C, LDM 81/562; D, LDM 81/566; E, LDM 81/77; F, LDM 81/73; G, H, PVL LDM 81/721 in ventral and lateral views. Ciecere River near Pavāri hamlet, Latvia. Ketleri Formation. Abbreviation: PVL, posterior ventro-lateral plate. Scale bars: 10 mm.

GEODIVERSITAS • 2001 • 23 (4) 591 Lukševičs E.

oa.AVL AB C D

vlr

oa.PVL

G E F

dc H

vlr oa.AVL

FIG. 76. — Bothriolepis ciecere Lyarskaja in Lyarskaja & Savvaitova, 1974; A-C, left-side PVL and D-H, right-side PVL in ventral (A-G) and lateral (H) views; A, LDM 81/73; B, LDM 81/77; C, LDM 81/76; D, LDM 81/300; E, LDM 81/75; F, LDM 81/302; G, H, LDM 81/78. Ciecere River near Pavāri hamlet, Latvia. Ketleri Formation. Abbreviations: AVL, anterior ventro-lateral plate; PVL, posterior ventro-lateral plate; dc, dorsal corner of lateral lamina; oa.AVL, area overlapped by AVL; oa.PVL, area overlapped by PVL; vlr, ventro- lateral ridge. Scale bar: 10 mm. is moderately high, 2.9 times as long as it is comprises 17-23% of total length of the ventral broad. The posterior oblique sensory line lamina. The ventral lamina 2-2.5 times as broad groove (dlg2) is not present almost in a half of as the lateral lamina high. The lateral lamina is specimens. In specimens LDM 81/211 low, 3-3.5 times as long as it is high. Both the (Fig. 72H) and 81/406, there is an additional right and left AVL could overlap the opposite branch of the posterior oblique dorsal sensory AVL. The axillary foramen (f.ax) is rather large, line groove dlg2’, which is parallel to dlg2. The slightly elongated and rounded in shape dorso-lateral ridge bears tubercles even in small (Lyarskaja & Savvaitova 1974). The visceral sur- individuals. The overlap area for the AMD is face of the AVL shows the high transverse ante- often restricted to half the length of the antero- rior crista (cit1) running antero-mesially parallel dorsal margin (LDM 81/422, 81/423), as in to the low and broad transverse thickening Remigolepis (Stensiö, 1931), or to the most part (cit2). of this margin (LDM 81/424). The PVL (Figs 75; 76) has similar proportions to The AVL (Figs 73A-D; 74) is of moderate the AVL, as in most Bothriolepis species. The breadth, the ventral lamina is 1.7-2.2 times as ventral lamina is 2-2.6 times as long as it is long as it is broad. The subcephalic division broad. The subanal division is relatively broad,

592 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

it occupies about one fifth (18-22%) of the total REMARKS PVL length. The lateral lamina is high, 1.8- Lyarskaja (Lyarskaja & Savvaitova 1974) des- 2.4 times long as it is high. The ventral lamina cribed two species: Bothriolepis ciecere and only 1.1 time as broad as the lateral lamina high. B. pavariensis on a base of material collected in The lateral lamina rather steep, the angle 1971 from the Pavāri locality. She claimed that between laminae is about 101°, but in no case B. pavariensis differs from B. ciecere in its 130° as indicated by Lyarskaja (Lyarskaja & 1) larger size; 2) the broader Prm; 3) the shape Savvaitova 1974). Both the right and left PVL of Pp; 4) the size and position of the external could overlap the opposite PVL. The ventro- openings for the endolymphatic ducts; 5) the lateral ridge (vlr) is strongly developed and proj- position and shape of a branches of the posterior ects from the plate as a sharp serrated keel along oblique sensory line groove; 6) the shape of the the subanal division. The MV with the L/B AMD (Lyarskaja & Savvaitova 1974). The index about 1.3 (Fig. 71H). description of B. pavariensis was based on three The pectoral fin (Figs 73E-G; 74E) is represent- poorly preserved specimens: part of head-shield ed by many disarticulated bones, and seven LDM 43/337, AMD 43-5082, and ADL 43-5095. specimens showing articulated plates of the In 1978, Lyarskaja collected additional material; proximal segment. There are two examples of the author collections from the type locality, the distal segments. Both segments bear promi- gathered in 1989, 1991, and 1995, and material nent lateral and mesial spines. On the proximal from the Ketleri locality, collected in 1984, 1995, segment the spines are large and closely setting. and 1999, largely expanded Bothriolepis materi- The proximal segment is not as broad as was als from the Ketleri Formation. The revision of claimed by Lyarskaja (Lyarskaja & Savvaitova all material allowed Lukševičs (1991) to suggest 1974: L/B index about 2), but is 3.5 times as long that only one species occurs in the Ketleri as it is broad. The CD1 is with L/B index vary- Formation. Mostly bones are from well-grown ing from 2.6 to 3.1 (2.9 on the average). The individuals of moderate size, but there are also shape and proportions of the other individual some quite large specimens. All specimen plates of the pectoral appendage are shown in described by Lyarskaja as B. pavariensis fit well Fig. 73. within the variation row of B. ciecere, and there The ornamentation is reticulate, anastomosing are no gaps in between these two forms neither in ridges are broken into shorter ridges on the the shape and proportions of individual plates, anterior part of the La and Prm and in large nor in the position of the sensory line grooves. specimens also on the Nu and Pp. The orna- The above mentioned distinctions between ment on the Sm consists of short ridges and B. pavariensis and B. ciecere could be explained tubercles, on the trunk-armour it is typically mostly by changes that take place during growth reticulate in general. In large specimens, the in Bothriolepis: size of the plates, shape of the reticulate ornament retained only on the cen- Prm, Pp, AMD; or by considerable intraspecific tral part of plates, whereas on the marginal variation characteristic for B. ciecere: the position parts of bones the anastomoses between ridges and shape of the posterior oblique sensory line reduse. On the AMD the ornament may consist groove. The following short description is the of ridges parallel to the margins of the plate, first full treatment in English, following but on the MxL and PVL there are short Lukševičs (1991) and considerably adding details ridges perpendicular to the dorso-lateral or to the description provided by Lyarskaja ventro-lateral ridge. The ornamentation of the (Lyarskaja & Savvaitova 1974). pectoral appendage is reticulate in general, radially arranged on the CD1. The network DISCUSSION ridges bear weak elevations in the points of Bothriolepis ciecere can be distinguished readily anastomoses on the ML2 and CV1. from B. leptocheira curonica and B. jani

GEODIVERSITAS • 2001 • 23 (4) 593 Lukševičs E.

(Lukševičs 1986), other Famennian Bothriolepis dence of a relationship between B. ciecere and representatives from the Main Devonian field, B. nielseni: affinity of their stratigraphical situa- and resembles B. ornata by some features. tion, as well as fact, that both B. ciecere and B. ciecere differs from B. ornata in its 1) smaller B. nielseni are the youngest species, the last rep- size; 2) shape and proportions of the Pn and resentatives of Bothriolepis in Baltic and Prm; 3) situation of the lateral pit on the La and Greenland respectively. postero-lateral corner of otico-occipital depression on the Pn; 4) development of the attachment area for the Sm on the La; 5) broader Bothriolepis sp. indet. 1 (Figs 77; 78) anterior margin of the AMD; 6) shape of the PMD; 7) strongly developed dorso-lateral and MATERIAL EXAMINED. — IEC LP 12-6, a Prm; ventro-lateral ridges. IEC LP 23-45, anterior part of the AVL; LP 32-1, 23-14, 2 Pn and Nu; IEC LP 23-37, prelateral plate; There are no species of Bothriolepis from several fragmentary bones of the trunk armour. Scotland (Miles 1968) similar to B. ciecere. LOCALITY AND HORIZON. — Quarry and mines not B. laverocklochensis Miles, 1968 from the far from Zarubino village approximately 25 km SE Rosebrae Beds differs from B. ciecere in the from Lyubitino town, Novgorod region, Russia; shape of PMD, absence of the crest on the upper Famennian. dorso-lateral ridge and presence of sharply defined dorsal median ridge. B. wilsoni Miles, DESCRIPTION 1968 has well-defined dorso-lateral ridge, how- IEC LP 12-6 is a relatively large Prm with ever clearly differs from B. ciecere in propor- typical reticulate ornamentation (Fig. 77A, B). tions of a head-shield bones, AMD and presence It is strongly vaulted both in longitudinal and of well-developed dorsal median ridge on transverse directions. The plate is broader AMD, as well as ornament. than it is long, maximum breadth (32.4 mm) The species B. ciecere and B. nielseni from exceeds the length (30.4 mm). The gently con- Greenland are clearly very close morphologi- vex rostral margin with weakly defined rostral cally. They are similar in the 1) general propor- angle is about 1.4 time longer than the wavy tions of the trunk-armour; 2) development of orbital margin, which bears the clearly defined the dorso-lateral ridge; 3) shape and proportions nasal notches. The infraorbital sensory groove of individual plates of the trunk-armour; (ifc1) crosses the lateral margin about a fourth 4) reticulate ornament. Unfortunately, B. nielseni of plate length from the rostral margin, but is represented only by the holotype which then strongly curves posteriorly and meets the consists of a crushed and flattened trunk- supraorbital canal (soc) behind the middle of armour and badly preserved parts of the head- the plate. The preorbital recess is of trifid shield and pectoral fin (Stensiö 1948). Absence type. of the description of the head-shield and the The Nu IEC LP 23-14 (Figs 77C; 78A) is mod- poor preservation of the type specimen does not erately broad as it is preserved, bears the moder- allow to compare both species with sufficient ately broad obtected nuchal area and detail. The distinctions between them are well-defined right lateral margin. The plate is insignificant and consist in that in B. nielseni broadest across the lateral corners. The posteri- 1) the dorsal wall of the trunk-armour is rela- or margin is almost straight and possess no pos- tively broader; 2) the posterior margin of the terior process. The central sensory line groove is AMD is longer; 3) the proximal segment of the clearly distinct. pectoral fin is more slender; 4) the ventro-lateral The Pn (Figs 77D; 78B-D) is of moderate ridge is not bearing the row of tubercles. It breadth, L/B index 80-96. The lateral division of seems likely that B. ciecere and B. nielseni are the Pn is relatively narrow composing 48% phylogenetically very close. There is good evi- of the general breadth of a plate. The postero-

594 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

A E C

A-C, E-G

B D FG

FIG. 77. — Bothriolepis sp. indet. 1; A, B, Prm IEC LP 12-6 in dorsal and visceral view; C, fragmentary Nu IEC LP 23-14; D, Pn IEC LP 23-1; E, anterior part of the AVL IEC LP 23-45 in ventral view; F, G, prelateral plate IEC LP 23-37 in dorsal and visceral view. Quarry near Zarubino village, Novgorod region, Russia. Upper Famennian. Abbreviations: AVL, anterior ventro-lateral plate; Nu, nuchal plate; Pn, paranuchal plate; Prm, premedian plate. Scale bars: 5 mm. lateral corner of otico-occipital depression otico-occipital depression; 4) similarly strong- (pr.po) is rounded and extends laterally over the ly defined dorso-lateral and ventro-lateral middle of the Pn’s posterior margin. ridges on the trunk armour; 5) similar orna- The AVL IEC LP 23-45 (Fig. 77E) is of moder- mentation, but differs in other shape of the ate breadth as it is preserved. The subcephalic Nu and Pn, as well as in more strongly arched division seems to be relatively short. The anteri- Prm. or lateral corner of subcephalic division is situated laterally from the middle between the median and lateral margins; it is developed into a Genus Grossilepis Stensiö, 1948 short process. Fragmentary MxL and PVL show TYPE SPECIES. — Grossilepis tuberculata (Gross, 1941). a well-developed keel on the dorso-lateral and ventro-lateral ridges. DIAGNOSIS. — Bothriolepididae in which the AMD The ornamentation is reticular, consisting of of an almost uniform breadth behind the postlevator processes, and normally overlaps both the ADL and large pits and quite coarse anastomosing ridges. MxL. The ADL and MxL also fairly uniform in width throughout their extent. REMARKS All specimens from Zarubino locality, collected by amateur collector, were grouped together Grossilepis tuberculata (Gross, 1941) because of typical reticular ornamentation with (Figs 79; 80) large pits between ridges. Bothriolepis tuberculata Gross 1941: 32-57, abb. 25, Bothriolepis sp. indet. 1 resembles Bothriolepis 26A-G, 27A-C, 28-43; taf. 18-28. ciecere in several features: 1) shape and pro- Bothriolepis cellulosa (Pander) – Gross 1932: 24 (p.p.); portions of the Prm; 2) proportions of the Pn; 1933: 36-39, taf. 4, fig. 5 (p.p.). — Obruchev 1947: 3) the position of the postero-lateral corner of pl. LV, fig. 4.

GEODIVERSITAS • 2001 • 23 (4) 595 Lukševičs E.

A csl B A

ifc1 mp nm d.end nm CD cr.pm ood

B C

cr.tv A, C, D nm mp

FIG. 78. — Bothriolepis sp. indet. 1; A, reconstruction of the Nu IEC LP 23-14; B, Pn IEC LP 23-1; C, D, Pn IEC LP 23-46 in vis- D ceral and dorsal view. Quarry near Zarubino village, Novgorod region, Russia. Upper Famennian. Abbreviations: Nu, nuchal plate; Pn, paranuchal plate; cr.pm, paramarginal crista; cr.tv, F transverse nuchal crista; csl, central sensory line groove; d.end, opening of canal for endolymphatic duct; ifc1, principal section E of infraorbital sensory line; mp, middle pit-line groove; nm, obtected nuchal area; ood, otico-occipital depression. Scale bars: 5 mm.

Grossilepis tuberculata (Gross) – Stensiö 1948: 524- 534, text-figs 26L, 28E, 35F, 36C-E, 39D, 41D, 43E, FIG. 79. — Grossilepis tuberculata (Gross, 1941); A, reconstruc- 44F, 45H, 47D, 48D, 53D, 266-271. tion of the head-shield; B, C, La; D, E, Pn; F, Nu (from Gross 1941: abb. 29 II, 27A, 27C, 26B, 26A, 25A respectively). Pērse HOLOTYPE. — AMD kept in SMNH (Gross 1941: River near Koknese (Kokenhusen), Latvia. Pļaviņas Formation. abb. 30F, taf. 21, fig. 1). Abbreviations: La, lateral plate; Nu, nuchal plate; Pn, paranuchal plate. Scale bar: 10 mm. MATERIAL EXAMINED. — LDM 65/77, MxL; NHM 17827, La; NHM 17811, 17817, 17820, three PMD; NHM 17812, PVL; LUGM, several unnumbered specimens including AMD, PMD, La plates is aaditional to that DIAGNOSIS. — Relatively small bothriolepidoid with described by Gross (1941) and Stensiö (1948). estimated length of dorsal wall of trunk armour reaching about 9 cm. Head-shield moderately vaulted with LOCALITIES AND HORIZON. — The type locality is an anterior margin much shorter than total breadth of the outcrop of dolomite, dolomite marl and clay at the plate. Postero-lateral corners of head-shield extends bank of Pērse River near Koknese, Latvia; The lower anteriorly to the level of the orbital fenestra posterior Frasnian Pļaviņas Formation. This species was found margin. Nu of moderate width, L/B index of about 61- in the Snetnaya Gora Member in several localities in 73, usually with concave posterior margin bearing the western and eastern Latvia: outcrops along Daugava median process, shallow postpineal notch on the ante- River from Kaktiņi to the ruins of Koknese castle, rior margin, slightly pronounced lateral and postero- exposures at Amata River not far from Kārļi and lateral corners. Pn with broad lateral division. Tergal along Mazā Jugla and Lielā Jugla Rivers, outcrops at angle situated between the anterior and middle thirds Venta River near Kuldīga and at Riežupe River of the AMD length. Posterior margin of AMD very (Sorokin 1978), Lithuania: borehole Berčiunai, 73-76 broad. Dorsal median ridge normally developed from m deep, borehole Pakapiai, 78.2-80.3 m deep, and the tergal angle backwards to the posterior corner of Pskov region of Russia: outcrop at the right bank of PMD. Dorsal corner slightly pronounced or some- Velikaya River near Piskovichi hamlet, Snetnaya times even not be clearly identifiable. Pectoral fin Gora, Pskov and Chudovo Beds of Russia. The fairly slender, proximal segment from 4.5 to slightly remains of G. tuberculata are very rare in the middle more than 5 times as long as broad. Lateral spines of part of the Pļaviņas Formation (Atzele and Sēlija the pectoral fin numerous, small, closely set and Members, which corresponds to the Pskov Beds in obtuse. Ornament consists of numerous closely and Russia) and until now reported only from eastern irregularly set pointed tubercles in well-grown Latvia (Sorokin 1978). individuals.

596 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

AB CFH ML3 CD3 CD1

ML4 MM4 ML2 cf.MxL CD4

MM2 SM DE CD2 AVL AMD G I ADL f.ax CV1 CD3 MM1 MM4 MV ML4 MxL

PMD ML2 CD4 MM2 PVL

CV2

FIG. 80. — Grossilepis tuberculata (Gross, 1941); A, B, AMD in dorsal (A) and visceral (B) views; C, specimen showing visceral and partly remained dorsal side of the AMD; D, reconstruction of dorsal wall of the trunk armour; E, reconstruction of ventral wall of the trunk armour; F, G, reconstruction of proximal segment of pectoral fin in dorsal and ventral views; H, I, parts of distal segment of pectoral fin in dorsal view. From Gross 1941: abb. 30F, 30A, 30D, 36, 37, 43A, 43B, 43F, 43H respectively. Pērse River near Koknese (Kokenhusen), Latvia. Pļaviņas Formation. Abbreviations: ADL, anterior dorso-lateral plate; AMD, anterior median dorsal plate; AVL, anterior ventro-lateral plate; CD1-4, dorsal central plates 1 to 4; CV1, 2, ventral central plates 1 and 2; ML2-4, lateral marginal plates 2 to 4; MM1, 2, 4, mesial marginal plates 1, 2 and 4; MV, median ventral plate; MxL, mixilateral plate; PMD, posterior median dorsal plate; PVL, posterior ventro-lateral plate; SM, semilunar plate; cf.MxL, area overlapping MxL; f.ax, axillary foramen.

REMARKS 524) was the same as that of the genus This species is well-described by Gross (1941) Grossilepis. and Stensiö (1948). Their descriptions are based on a large collection of the placoderm and other DISCUSSION fish remains kept at Swedish Museum of The comparison of Grossilepis tuberculata with Natural History, Stockholm. Although little G. spinosa is provided below the description of new material is available that has not been the latter. G. tuberculata differs well from described before, the descriptions of Gross and G. brandi Miles, 1968 in its relatively narrower Stensiö can be added, providing a new definition Nu and a proportions of the anterior and of this species, as the definition of Grossilepis posterior divisions of the lateral margin of this tuberculata suggested by Stensiö (1948: 523- plate.

GEODIVERSITAS • 2001 • 23 (4) 597 Lukševičs E.

A LOCALITIES AND HORIZON. — The type locality is an outcrop containing red-grey sandstone at the right bank of Imula River near Ģenduļi and Bienes hamlets, D Latvia. Some specimens were collected from the Velna Ala site at the left bank of Abava River. The middle Frasnian Ogre Formation.

DIAGNOSIS. — A small bothriolepidoid with estimated length of dorsal wall of trunk armour reaching about 6 cm. Nu is moderately wide with B/L index of B 62 in holotype, with convex posterior margin bearing the sharp median process, shallow postpineal notch on the anterior margin, slightly pronounced postero- lateral corners and well-defined lateral corners. Clearly defined lateral corner is slightly pronounced. Lateral spines of ML2 are strikingly long and pointed. Ornament consists of numerous closely and irregularly set tubercles.

C DISCUSSION Grossilepis spinosa resembles Grossilepis tuberculata by several features, but could be readily distinguished from it in its 1) other shape of the Nu and its posterior margin; 2) character and shape of strongly developed long lateral spines of the proximal segment of pectoral fin. Grossilepis spinosa differs well from G. brandi in its relatively narrower Nu and a proportions of the anterior and posterior divisions of the lateral margin of this plate.

REMARKS This species was established by Gross (1942) as belonging to the genus Bothriolepis, but Stensiö (1948) suggested it is fairly close to Grossilepis

FIG. 81. — Grossilepis spinosa (Gross, 1942); A, Nu; B, fragmen- tuberculata. Grossilepis spinosa shows some fea- tary La; C, anterior part of AMD in ventral view; D, ML2. From tures characteristic for the genus Grossilepis as Gross 1942: abb. 9A-D. Imula River near Lankserde hamlet, Latvia. Ogre Formation. Abbreviations: AMD, anterior median the shape of the AMD, sutural connections dorsal plate; ML2, lateral marginal plate 2; La, lateral plate; between the AMD and MxL, as well as tubercu- Nu, nuchal plate. late ornamentation.

Grossilepis spinosa (Gross, 1942) INTERRELATIONSHIPS OF BALTIC (Fig. 81) BOTHRIOLEPIDS Bothriolepis spinosa Gross 1942: 418-420, abb. 9A-D. There is no widely adopted classification of placoderms (Obruchev 1964; Miles 1968; Denison Grossilepis(?) spinosa (Gross) – Stensiö 1948: 615. 1978, 1983; Young 1984a; Goujet & Young HOLOTYPE. — Nu kept in SMNH. 1995; Janvier 1996); placoderm groups are being

MATERIAL EXAMINED. — The specimens described subdivided using strongly differing criteria. The and illustrated by Gross (1942), kept at SMNH. classification of Obruchev (1964) has been used

598 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

in the Russian paleoichthyological literature Sinolepidida, Bothriolepidida and Asterole- (e.g., Karatajūte-Talimaa 1963, 1966; Malinov- pidida. skaya 1977; Lyarskaja 1981) with the class Young (1984a) also supported such a scheme, Placodermi divided into two subclasses: suggesting four groups in the antiarch clado- Arthodira and Antiarcha including respectively gram: yunnanolepids, sinolepids, asterolepi- ten and two orders (Asterolepidida and doids and bothriolepidoids, uniting the three Remigolepidida). Antiarchs have been regarded latter into an euantiarch group. as order (Denison 1978, 1983), or sister group of Zhang Guorui (1984) introduced the new Euarthrodira (Young 1984), sister group antiarch order Procondylolepiformes, including Palaeacanthaspida (Goujet 1984) or Arthrodira the new family Procondylolepidae. Later, Pan et and some other groups of Placodermi, but not al. (1987) referred the family Procondylolepidae all Arthrodira sensu Obruchev (Gardiner 1984). to Euantiarcha. Tong-Dzuy & Janvier (1990) Recently Goujet & Young (1995) proposed a noted that Procondylolepis from China is closely new scheme of the interrelationships of placo- related or similar to Chuchinolepis Chang, 1978 derms. According to their analysis, the from Vietnam; both are characterized by a Antiarcha are placed between the tesserate weakly developed primitive processus brachialis. forms (Acanthothoraci and Rhenanida) and They therefore referred Procondylolepis Zhang, other, more advanced placoderms. 1984 to the family Chuchinolepidae. Novitskaya (1986) claimed that she found the Zhang Guorui & Young (1992) analysed the dis- outer hypophyseal opening in two specimens of tribution of several characters within 13 genera, Asterolepis ornata. This opening, she claimed, producing four cladograms of possible bothri- pierces “the bottom of praenasal pit” under the olepidoid interrelationships. nasal openings and is situated between them Adding recently described taxa to the scheme (Novitskaya 1986: fig.1zh; Novitskaya & proposed by Young (1984a), their phylogenetic Karatajūte-Talimaa 1989: fig. 3; pl. 1, fig. 1). position is tentatively envisaged in Fig. 82. Reexamination of the described specimens and Four genera are concerned, each author refer- additional excellently preserved material on ring them to bothriolepid: Vietnamaspis Asterolepis ornata kept in the LDM reveals no described by Long et al. (1990), Jiangxilepis evidence of such a canal. The slight pit between from China (Zhang & Liu 1991), Tenizolepis the Prm and Ro in described specimen is proba- from Kazakhstan (Malinovskaya 1977), bly a misinterpreted preparation mark in the Kirgisolepis from Kirgizia (Panteleyev 1993) remained clay matrix. The praenasal (anterior) are also included here. Nevertheless, wall of the rostral plate is closely fitted to the Tenizolepis and Kirgizolepis are characterized vertically directed posterior wall of the Prm, by primitive features distinguishing them from leaving no place for a canal (Lukševičs 1999b). Bothriolepis but being closer to Dianolepis Miles (1968) divided the antiarchs into subor- Chang, 1965: Pp is broad and makes contact ders Asterolepidoidei, Bothriolepidoidei and with the La; the relatively short pectoral Yunnanolepidoidei. Denison (1978) considered appendages do not reach the posterior margin yunnanolepids as belonging to the family of the trunk-shield; and CD1 has a common Bothriolepididae, and additionally accepted two suture with CD2. more families: Asterolepididae and Sinole- Several recent publications have been dealt with pididae. Janvier & Pan Jiang (1982), following the interrelationships of placoderms and partic- Miles, regarded Yunnanolepis Liu, 1963 as a ularly bothriolepids (Long 1983; Long & very primitive and separate genus, characterized Werdelin 1986; Young 1984a, 1988). Young by absence of processus brachialis, and referred it (1988) paid great attention to three aspects of to a separate order. The other antiarchs were bothriolepid antiarch morphology: the structure united into group Euantiarcha including of preorbital recess, submarginal attachment to

GEODIVERSITAS • 2001 • 23 (4) 599 Lukševičs E.

39-40 38 Remigolepis 35-37 Pambulaspis Asterolepis 28-32 Pterichthyodes Byssacanthus Stegolepis Asterolepidoids 33 Sherbonaspis Asperaspis 34 Gerdalepis Grossaspis Lepadolepis 9-11 Grossilepis 27 Bothriolepis 26 Vietnamaspis 25 Monarolepis Dianolepis Bothriolepidoids 20-24 Jiangxilepis Kirgisolepis 8 Tenizolepis Microbrachius EUANTIARCHS 12, 13 Wudinolepis 14-19 Sinolepis Xichonolepis Sinolepids Vanchienolepis Grenfellaspis 1-7 Chuchinolepis Procondylolepids Procondylolepis ? Phymolepis Yunnanolepis Yunnanolepids Zhanjilepis Qujinolepis

FIG. 82. — Cladogram for antiarch genera, modified after Young (1988). For synapomorphies 1-40 see Young (1984). the skull, and ontogenetic change in the shape of from the other areas it is known in the Antarctic the AMD. He suggested four types of preorbital species B. askinae Young, 1988, as well as in recess and named them as “simple”, “trilobate”, B. volongensis Lyarskaja & Lukševičs, 1999 (see “pentagonal”, and “trifid”. The simple recess is Lukševičs & Sorokin 1999) from North Timan. the semicircular form of Long (1983). Stensiö The trilobate recess, which is distinguished from (1948) and Miles (1968) have described the the simple recess by having an anteriorly preorbital recess of the most simple shape with- protruded middle part on the Prm, is so far out lateral and median extensions or “horns” as unknown in Baltic species, being reported from the “canadensis-type” because it was first B. hydrophyla and B. alvesiensis Stensiö, 1948 described in detail for B. canadensis. Among the from Scotland, and B. barretti Young, 1988 Baltic species the simple recess is found in from the Antarctic. The pentagonal recess has earliest representatives of the genus: B. prima, well-defined lateral and median angles, the later- B. obrutschewi, B. cellulosa, B. traudscholdi, and al angle being about 90°. This type of recess is

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u B. ciecere t B. nielseni s B. jani B. ornata B. groenlandica o B. leptocheira B. jarviki p B. grenfellensis B. tatongensis q B. maxima B. gigantea n r B. zadonica B. wilsoni B. nitida B. coloradensis B. hicklingi B. hayi B. taylori h l B. macphersoni m B. karawaka B. longi i k B. kohni B. portalensis B. niushoushanensis k B. vuwae j B. mawsoni B. paradoxa d B. obesa B. evaldi f, g B. cullodenensis B. gippslandiensis B. barretti e B. hydrophyla c B. alvesiensis B. fergusoni B. volongensis B. trautscholdi b B. canadensis B. cellulosa a B. panderi B. obrutschewi 27 B. prima B. askinae Grossilepis

FIG. 83. — Cladogram for various species of Bothriolepis, added by bothriolepids from Baltic area and Australia (Johanson 1997, 1998; Johanson & Young 1999), and modified after Young (1988). Synapomorphies are: a, AMD in adults broadest across lateral corners, and MxL broadest through its dorsal corner; b, lateral corners on AMD appear early in ontogeny; c, point contact between MM1 and CV2 of pectoral fin, to separate CV1 from MM2; d, axillary foramen longer than high; e, trilobate preorbital recess; f, trunk armour with pronounced median dorsal crest; g, short, deep Sm; h, pentagonal preorbital recess; i, anterior Sm attachment supported by a separate ridge in transverse lateral groove; j, squarish Nu with convex anterior division of the lateral margin and short postero-lateral corners; k, elongation of preorbital region of skull; l, separate triangular and ventrally-facing attachment surface for Prl on La; m, anterior portion of posterior submarginal attachment covers spiracular groove; n, trifid preorbital recess; o, slender proximal segment of pectoral fin; p, orbital margin of Pp at the level of lateral corners of head-shield; q, branch of the infraorbital sensory line diverging on the Prl parallel to rostral margin of head-shield; r, massive, low and broad median dorsal crest on AMD; s, thickened bone edges on orbital margins of Prm and La plates; t, crista transversalis anterior transversely oriented parallelly to cit2 on visceral surface of ventral lamina of AVL; u, ventro-lateral ridge is making a keel. Abbreviations: AMD, anterior median dorsal plate; AVL, anterior ventro-lateral plate; CV1, 2, ventral central plates 1 and 2; MM2, mesial marginal plate 2; MxL, mixilateral plate; cit2, transverse thickening; La, lateral plate; Nu, nuchal plate; Pp, postpineal plate; Sm, submarginal plate. known in many Antarctic species such as B. por- was previously described as the “groenlandica- talensis Young, 1988, B. karawaka and type” (Stensiö 1948; Miles 1968). It differs from B. macphersoni (see Young 1988). The trifid recess the pentagonal recess in the more acute and

GEODIVERSITAS • 2001 • 23 (4) 601 Lukševičs E.

elongated lateral angles, and the development of retrieved with parsimony softs (PAUP, etc.). So angular indentations on the anterolateral mar- in agreement with the editor we decided not to gins of the recess, forming three projections into publish this result until a more complete and the Prm and La. The trifid recess is known in testable parsimony analysis has been run. several species of Bothriolepis from Baltic, such A new version of the interrelationship clado- as B. maxima, B. leptocheira, B. ornata, and gram for the best known bothriolepids has been B. ciecere. B. jani has probably the recess of completed by including in Young’s cladogram intermediate type between pentagonal and trifid the Baltic species of Bothriolepis. Unfortunately types, with short lateral horns, but broad anteri- several bothriolepid taxa from China and or projection. The trifid recess have been report- Kazakhstan have been poorly described and ed also in B. jarviki, B. gigantea, B. leptocheira, could therefore not be included in the analysis. B. hayi, and B. hicklingi from Scotland (Miles Interrelationships among 44 bothriolepidid taxa 1968), B. nitida (Leidy, 1856) from Pennsylvania (Grossilepis tuberculata and 43 species of (Young 1988), B. groenlandica from East Bothriolepis) are presented in Fig. 83 (the last Greenland (Stensiö 1948), B. grenfellensis appearance of the cladogram has been prepared Johanson, 1997, B. yeungae Johanson, 1998 and manually due to insufficient amount of analysed probably B. tatongensis Long & Werdelin, 1986 characters and too large number of species). from Australia. Grossilepis tuberculata has been used in the The simple recess is considered to be plesiomor- analysis as a sister group of Bothriolepis. It dif- phic (Long 1983; Young 1988). Regarding the fers from the species of Bothriolepis in the occurrence of this type of recess among the absence of lateral corners of the AMD. Among Baltic species, it is known only from specimens the other taxa in the analysis, B. askinae shows belonging to the possibly uppermost Middle unusual changes of shape of the trunk armour Devonian or lowermost Upper Devonian plates during ontogeny with the AMD develop- Amata Formation (B. prima, B. obrutschewi), ing the lateral corners at a late stage (Young and lower/middle Frasnian (B. cellulosa, 1988). All the other Bothriolepis probably have B. traudscholdi). The trifid recess appears in lateral corners of AMD which appear earlier in Baltic species of Bothriolepis rather later than in ontogeny and Young (1988) has suggested this Australian forms: recess of trifid type occurs for feature is a synapomorphy of these species the first time in B. maxima from the upper which compose a monophyletic group. Frasnian, whereas among the bothriolepids Bothriolepis prima and B. obrutschewi have from western Australia “Bothriolepis sp. from pectoral fins with the CV1 making contact Gogo […] (Young 1984b), represents one of the with the MM2. All the remaining species pos- earliest well-dated occurrences (early Frasnian) sess a point contact between the MM1 and of the trifid recess” (Young 1988: 111). CV2 of the pectoral fin, to separate the CV1 Long (1983) published a cladogram based from the MM2. mainly on the preorbital recess shape, including Most species of Bothriolepis have an axillary 18 species of Bothriolepis. Young (1988) added foramen longer than high. Species of the Antarctic species to this cladogram and, Bothriolepis with a simple recess and elongated using several additional characters, analyzed the axillary foramen could be subdivided into two interrelationships of 37 species in total. groups. B. cullodenensis Long, 1983 and B. gipp- A list of 20 characters (see Appendix) summa- slandiensis Hills, 1929 could be united into a rizing their distribution in Bothriolepis species separate clade sharing a pronounced median from Baltic and NW Russia has been established dorsal crest on the trunk armour (Long & in order to run a phylogenetic analysis. Werdelin 1986; Young 1988). Within this group, Unfortunately the unique and pectinate tree B. gippslandiensis acquires through reversal a resulting from the PHYLIP analysis has not been character otherwise seen in more primitive

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members of the genus like B. prima and toral fin, position of the branch of the infra- B. obrutschewi, namely a CV1-MM2 contact in orbital sensory line diverging on the Prl, the the pectoral fin. presence of a massive, low and broad dorsal About three quarters of all the species of crest on the trunk armour, and the appearance Bothriolepis included in the analysis have the of thickened bone edges on the orbital margin of more complex preorbital recess. As it is already the Prm and La. The last feature probably mentioned, B. barretti, B. hydrophyla and appears twice during the phylogenetic develop- B. alvesiensis have a trilobate preorbital recess. ment of the group, as it occurs not only in those The members of this clade have been reported species of Bothriolepis which have a trifid preor- from Scotland and Antarctic. The group pos- bital recess and appear very late, in the middle- sessing the pentagonal preorbital recess is subdi- late Famennian (B. ornata, B. groenlandica, vided into four clades. B. evaldi seems to be the B. jani, B. nielseni, B. ciecere), but also in B. mac- most primitive member of the group. The phersoni, B. karawaka and B. niushoushanensis. largest clade is characterized by the presence of The proposed result of the analysis fits well with a trifid preorbital recess. The second largest those presented by Young (1988). The phyloge- clade is characterized by the nature of the cheek netic analysis of Bothriolepis species from several attachment, which was proposed by Young continents leads to the conclusion that an isola- (1988) as useful for delineating species groups tion between the ichthyofaunas occured in within Bothriolepis. B. macphersoni, B. karawaka, Gondwana and Laurussia and probably was more B. kohni, B. portalensis Young, 1988 from obvious during the Givetian-early Frasnian than Antarctica, and B. niushoushanensis Pan et al., during the late Frasnian-Famennian. This con- 1980 from North China, have an anterior Sm clusion seems to be corroborated by the distri- attachment supported by a separate ridge in the bution of the Tristichopteridae, a group of transverse lateral groove on the visceral surface Sarcopterygians which probably originated and of the head shield. Among them, B. macphersoni initially evolved in the Laurussian continent, and B. karawaka possess a separate triangular and achieved a wider distribution including and ventrally-facing attachment surface for the Gondwana during the late Frasnian or early Prl on the lateral margin of the La. The next Famennian (Ahlberg & Johanson 1997). clade of Bothriolepis having a pentagonal preorbital recess is characterized by the squarish Nu Acknowledgements with convex anterior division of the lateral mar- I wish to thank Drs V. Talimaa, D. Goujet, gin and short postero-lateral corners, a set of L. Lyarskaja, E. Kurik, A. Ivanov, O. Lebedev features first used by Young (1988) in his analy- for useful discussion; Mr B. Pogrebov, sis. This clade includes two species from Mr H. Birznieks and Mrs I. Novicka for their Scotland, namely B. obesa Traquair, 1888 and photography. I am greatly indebted for making B. paradoxa, as well as two taxa from Antarctica possible my access to collections under their (B. mawsoni Young, 1988 and B. vuwae Young, supervision and for the loan of specimens to 1988). Somewhat surprisingly, the analysis fails Dr V. Talimaa, Institute of Geology of Lithuania, to unite B. kohni and B. portalensis with Vilnius; Dr V. Sorokin and Mrs I. Upeniece, B. vuwae and B. mawsoni, even though all share Institute of Geology of the University of Latvia, an elongated preorbital region of the skull with Rīga; Mrs I. Blueman and Dr Zh. Polyarnaya, a long and narrow Prm. Mining Museum, Saint-Petersburg; Dr A. Ivanov, Finally it should be noted that the group of Institute of the Earth Crust, St.-Petersburg; Bothriolepis species with a trifid preorbital Dr O. Lebedev, Paleontological Institute of RAS, recess contains members from both Laurussia Moscow; Dr P. Forey and Dr P. E. Ahlberg, and Gondwana, and could be delineated using Natural History Museum, London; Dr M. Taylor such a characters as the elongation of the pec- and Dr R. Patton, National Museums of

GEODIVERSITAS • 2001 • 23 (4) 603 Lukševičs E.

Scotland, Edinburgh. I would like to thank EICHWALD E. 1840. — Die Tier- und Pflanzenreste Dr O. Lebedev and Dr P. E. Ahlberg for the lin- des alten roten Sandsteins und Bergkalks im Nowgorodschen Gouvernement. Saint-Petersburg guistic correction of the text of my Dr geol. Academy Imperial of Sciences, Bulletin of Sciences 7 thesis, which give the base for this paper. (150, 151): 78-91. Dr G. Young is warmly thanks for critical EICHWALD E. 1844a. — Über die Fische des vor- review of the first version of the manuscript and weltlichen Ozeans in der Umgebung von Pawlowsk. Otechestvenniye Zapiski 36. great job improving my English. Dr H. Lelièvre EICHWALD E. 1844b. — Über silurisch-devonischen revised the phylogenetic analysis. Schichten im Petersburger Gouvernement und auf den Inseln der Ostsee. Neues Jahrbuch Mineralogie, Geologie, Paläontologie 1: 41-48. EICHWALD E. 1860. — Lethaea Rossica ou palaeon- REFERENCES tologie de la Russie. Premier volume. Ancienne période. Stuttgart, 59 pls. AGASSIZ L. 1844-1845. — Monographie des poissons EICHWALD E. 1861. — Russian Paleontology. Ancient fossiles du vieux Grès rouge, ou Système dévonien period. Saint-Petersburg, 521 p. (in Russian). des Îles Britanniques et de Russie. Neuchâtel, ESIN D., GINTER M., IVANOV A., LEBEDEV O., Soleure, chez Gent & Gassman, xxxvi + 171 p., LUKŠEVIČS E., AVKHIMOVICH V., GOLUBTSOV V. & atlas, 43 pls. PETUKHOVA L. 2000. — Vertebrate correlation of AHLBERG H. E. & JOHANSON Z. 1997. — Second tris- the Upper Devonian and Lower Carboniferous on tichopterid (Sarcopterygii, Osteolepiformes) from the East European Platform. Courier Forschung- the Upper Devonian of Canowindra, New South sinstitut Senckenberg 223: 341-359. Wales, Australia, and phylogeny of the FELSENSTEIN J. 1993. — PHYLIP (Phylogeny Tristichopteridae. Journal of Vertebrate Inference Package) version 3.5c. Department of Paleontology 17 (4): 653-673. Genetics, University of Washington, Seattle [dis- AHLBERG P. E., LUKŠEVIČS E. & LEBEDEV O. 1994. — tributed by the author]. The first tetrapod finds from the Devonian (Upper GAILĪTE L. I., KURŠS V., LUKŠEVIČA L., LUKŠEVIČS E., Famennian) of Latvia. Philosophical Transactions of POMERANCEVA R., SAVAITOVA L., STINKULIS Ģ., the Royal Society of London 343 (B): 303-328. ZABELE A. 2000. — Legends for geological maps of ANDREWS S. M. 1982. — The Discovery of Fossil Latvian bedrock. Rīga, State geological survey, 101 p. Fishes in Scotland up to 1845 with Checklist of GARDINER B. G. 1984. — The relationship of Agassiz’s Figured Specimens. Royal Scottish Placoderms. Journal of Vertebrate Paleontology 4 Museum, Edinburgh, 87 p. (3): 379-395. AVKHIMOVITCH V. I., TCHIBRIKOVA E. V., GOUJET D. F. 1984. — Placoderm interrelationships: OBUKHOVSKAYA T. G., NAZARENKO A. M., a new interpretation, with a short review of placo- UMNOVA V. T., RASKATOVA L. G., MANTSUROVA derm classification. Proceedings of the Linnean V. N., LOBOZIAK S. & STREEL M. 1993. — Middle Society of N.S.W. 107 (3): 211-243. and Upper Devonian miospore zonation of GOUJET D. & YOUNG G. 1995. — Interrelationships of Eastern Europe. Bulletin des Centres de Recherche Placodermi revisited, in LELIÈVRE H., WENZ S., Exploration-Production Elf Aquitaine 17 (1): 79- BLIECK A. & CLOUTIER R. (eds), Premiers Verté- 147. brés et Vertébrés inférieurs. Geobios M.S. 19: 89-96. BLIECK A., GOLSHANI F., GOUJET D., HAMDI A., GRAHAM-SMITH W. 1978. — On some variations in JANVIER PH., MARK-KURIK E. & MARTIN M. the latero-sensory lines of the placoderm fish 1980. — A new vertebrate locality in the Eifelian of Bothriolepis. Philosophical Transactions of the the Klush-Yeilagh formation, eastern Alborz, Iran. Royal Society of London B 282: 1-39. Palaeovertebrata 9 (5): 133-155. GROSS W. 1931. — Asterolepis ornata Eichw. und das BLIECK A., TURNER S. & YOUNG G. (eds) 2000. — Antiarchi-Problem. Palaeontographica 75: 1-62. Devonian vertebrate biochronology and global GROSS W. 1932. — Fossilium Catalogus. Pars 57: marine/non-marine correlation. Courier Forschung- Antiarchi. W. Junk, Berlin, 40 p. Institut Senckenberg 220: 161-193. GROSS W. 1933. — Die Fische des Baltischen Devons. DENISON R. H. 1978. — Placodermi, in SCHULTZE H. Palaeontographica 79: 1-74. P. (ed.), Handbook of Paleoichthyology. Volume 2. GROSS W. 1941. — Die Bothriolepis-Arten der Gustav Fischer, Stuttgart, 128 p. Cellulosa-Mergel Lettlands. Kungl. Svenska DENISON R. H. 1983. — Further consideration of Vetenskaps-akademiens Handlingar 19 (5): 1-79. Placoderm evolution. Journal of Vertebrate GROSS W. 1942. — Die Fischfaunen des baltischen Paleontology 3 (2): 69-83. Devons und ihre biostratigraphische Bedeutung. EFREMOV J. A. 1940. — Taphonomy: new branch of Korrespondenz-blatt des Naturforscher-Vereins zu paleontology. Pan-American Geologist 74: 81-93. Riga 64: 373-436.

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WERDELIN L. & LONG J. 1986. — Allometry in the YOUNG G. C. 1991. — Fossil fishes from Antarctica, placoderm Bothriolepis canadensis and its signifi- in TINGEY R. J. (ed.), The Geology of Antarctica. cance to antiarch evolution. Lethaia 19 (2): 161-169. Oxford Monographs in Geology and Geophysics WOODWARD A. S. 1891. — Catalogue of the Fossil 17, Clarendon Press, Oxford University Press, Fishes in the British Museum (Natural History). 2. Oxford: chapter 15, 538-567. London, 567 p. YOUNG G. C. & GORTER J. D. 1981. — A new fish YOUNG G. C. 1974. — Stratigraphic occurence of fauna of Middle Devonian age from the some placoderm fishes in the Middle and Late Taemas/Wee Jasper region of South Wales. Bureau Devonian. Newsletter of Stratigraphy 3, 4: 243-261. of Mineral Resources, Australia, Bulletin 209: 83-147. YOUNG G. C. 1984a. — Comments on the phylogeny YOUNG G. & ZHANG G. 1992. — Structure and func- and biogeography of antiarchs (Devonian placo- tion of the pectoral fin and operculum in antiarchs, derm fishes), and the use of fossils in biogeogra- Devonian placoderm fishes. Palaeontology 35, part phy. Proceedings of the Linnean Society of N.S.W. 2: 443-464. 107 (3): 443-473. ZHANG G. 1978. — The antiarchs from the Early YOUNG G. C. 1984b. — Reconstruction of the jaws Devonian of Yunnan. Vertebrata PalAsiatica 16: and braincase in the Devonian Placoderm fish 147-186 (in Chinese with English summary). Bothriolepis. Palaeontology 27, part 3: 635-661. ZHANG G. 1984. — New form of Antiarchi with YOUNG G. C. 1986. — Early Devonian fish material primitive brachial process from Early Devonian of from the Horlick Formation, Ohio Range, Yunnan. Vertebrata PalAsiatica 22: 81-91 (in Antarctica. Alcheringa 10 (1-2): 35-44. Chinese with English summary). YOUNG G. C. 1987. — Devonian fish remains from ZHANG G. & LIU Y.-G. 1991. — A new Antiarch Billiluna, eastern Canning Basin, Western from the Upper Devonian of Jiangxi, China, in Australia. BMR Journal of Australian Geology and CHANG M. M., LIU Y. H. & ZHANG G. R. (eds), Geophysics 10 (2): 179-192. Early Vertebrates and Related Problems of YOUNG G. C. 1988. — Antiarchs (Placoderm fishes) Evolutionary Biology. Science Press, Beijing: 195- from the Devonian Aztec Silstone, Southern 212. Victoria Land, Antarctica. Palaeontographica 202 ZHANG G. & YOUNG G. C. 1992. — A new antiarch (A): 1-125. (placoderm fish) from the Early Devonian of South YOUNG G. C. 1990. — New Antiarchs (Devonian China. Alcheringa 16: 219-240. Placoderm fishes) from Queensland, with com- ŽEIBA S. & VALIUKEVIČIUS J. 1972. — New data on ments on Placoderm phylogeny and biostratigra- the Famennian conodont fauna of the southern phy. Memoirs of the Queensland Museum 28 (1): Peribaltic. Geografiya i Geologiya IX: 167-171 (in 35-50. Russian, with Lithuanian and German abstracts).

Submitted on 13 April 1999; accepted on 23 April 2001.

608 GEODIVERSITAS • 2001 • 23 (4) Bothriolepids (Vertebrata, Placodermi) from the Devonian of Baltic

APPENDIX

List of characters summarizing character distribution in 5. Pectoral pit-line traced on the CV1 continuing on the Bothriolepis from Baltic and NW Russia. 0, absent; CV2. 1, present; ?, unknown character state. The characters 6. Obtected nuchal area present on Pn. have been defined for future parsimony analysis as a run 7. Trifid preorbital recess. of the matrix with the PHYLIP package gave one solution 8. Thickened bone edges on orbital margins of Prm corresponding to a totally pectinated topology. This and La plates. solution is not retrieved with the same matrix in PAUP 9. Long middle pit-line and supraoccipital sensory which proposed a fully unresolved topology. In agree- grooves present. ment with the author, the phylogenetic part is not publi- 10. Short Sm plate. shed as previously envisaged. Abbreviations: AMD, 11. Crista transversalis anterior transversely oriented anterior median dorsal plate; AVL, anterior ventro-lateral (parallel to cit2) on ventral lamina of AVL. plate; CD5, dorsal central plate 5; cit2, transverse thicke- 12. Branch of the infraorbital sensory line diverging on ning on the visceral surface of AVL; CV1, 2, ventral central the Prl parallel to the rostral margin of the head-shield. plates 1, 2; La, lateral plate; MM1, 2, mesial marginal 13. Squarish Nu with convex anterior division of the plates 1, 2; MxL, mixilateral plate; Nu, nuchal plate; Pmg, lateral margin and short postero-lateral corners. postmarginal plate; Pn, paranuchal plate; Pp, postpineal 14. CD5 present in distal segment. plate; Prl, prelateral plate; Prm, premedian plate; 15. Pmg of trapezoid rather than of rhomboid shape. Sm, submarginal plate; B., Bothriolepis; G., Grossilepis. 16. Main lateral line canal reaches the posterior margin of the MxL plate. 1. AMD in adults broadest across lateral corners, and 17. Trunk-armour with pronounced median dorsal crest. MxL broadest through its dorsal corner. 18. Pp orbital margin at the level of lateral corners of the 2. Lateral corners on AMD appear early in ontogeny. head-shield. 3. Point contact between Mm1 and CV2 plates of pec- 19. Long branch of the infraorbital sensory line diverging toral fin, to separate CV1 from MM2. on the Prl. 4. Axillary foramen longer than high. 20. Ventro-lateral ridge makes a keel.

Taxon 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

G. tuberculata (Gross, 1941) 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 B. prima Gross, 1942 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 B. obrutschewi Gross, 1942 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 B. cellulosa 11100000000000000000 (Pander in Keyserling, 1846) B. panderi Lahusen, 1880 1 1 ? ? ? ? 0 0 0 0 ? 0 0 0 0 0 0 0 0 0 B. traudscholdi Jaekel, 1927 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 B. maxima Gross, 1933 1 1 1 1 1 1 1 0 0 0 0 1 0 0 0 0 0 0 0 0 B. evaldi Lyarskaja, 1986 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 B. leptocheira Traquair, 1893 1 1 1 1 1 1 1 0 1 ? 0 0 1 1 1 0 0 0 0 0 B. ornata Eichwald, 1840 1 1 1 1 1 1 1 1 0 1 0 0 0 0 0 0 0 0 0 0 B. jani Luksevics, 1986 1 1 1 1 ? 1 1 1 1 ? 1 0 0 0 0 1 0 0 0 0 B. heckeri n. sp. 11????1????0000?111? B. ciecere Lyarskaja 1 1 1 1 1 1 1 1 0 1 1 0 0 0 0 0 0 0 0 1 in Lyarskaja & Savvaitova, 1974

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